{"id":220575,"date":"2025-03-04T02:36:18","date_gmt":"2025-03-04T02:36:18","guid":{"rendered":"https:\/\/www.solinst.com\/ph-sensors\/"},"modified":"2026-05-07T21:47:22","modified_gmt":"2026-05-07T21:47:22","slug":"ph-sensors","status":"publish","type":"page","link":"https:\/\/www.solinst.com\/en-gb\/products\/solinst-eureka\/water-quality-sensors\/ph-sensors\/","title":{"rendered":"pH Sensors"},"content":{"rendered":"<p>[et_pb_section fb_built=&#8221;1&#8243; fullwidth=&#8221;on&#8221; disabled_on=&#8221;on|on|on&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; disabled=&#8221;on&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_fullwidth_image src=&#8221;https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/03\/5001-easy-probe-water-quality-sonde-1920&#215;500-1.webp&#8221; alt=&#8221;solinst eureka easyprobe water quality sondes&#8221; title_text=&#8221;Solinst Eureka EasyProbe Water Quality Sondes&#8221; src_tablet=&#8221;https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/03\/5001-easy-probe-water-quality-sonde-965&#215;500-1.webp&#8221; src_phone=&#8221;https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/03\/5001-easy-probe-water-quality-sonde-965&#215;500-1.webp&#8221; src_last_edited=&#8221;on|phone&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_fullwidth_image][\/et_pb_section][et_pb_section fb_built=&#8221;1&#8243; admin_label=&#8221;H1 and breadcrumbs&#8221; _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;792ca5bd-0808-46bd-9ce7-3bcb8e74f4d3&#8243; global_colors_info=&#8221;{}&#8221;][et_pb_row _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;4b28f470-0d73-4e9d-b92d-e6f41f2cea24&#8243; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;4_4&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;3078f328-b50a-467d-9906-3143dabcd7ac&#8221; header_text_align_tablet=&#8221;&#8221; header_text_align_phone=&#8221;&#8221; header_text_align_last_edited=&#8221;on|desktop&#8221; header_font_size_tablet=&#8221;30px&#8221; header_font_size_phone=&#8221;26px&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<h1 role=\"heading\" aria-level=\"2\" data-uw-rm-heading=\"level\">pH Sensor: Water Quality Probe<\/h1>\n<p>[\/et_pb_text][dsm_breadcrumbs disabled_on=&#8221;on|off|off&#8221; _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;default&#8221; home_icon_text_color=&#8221;#d6d6d6&#8243; global_colors_info=&#8221;{}&#8221;][\/dsm_breadcrumbs][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=&#8221;1&#8243; admin_label=&#8221;Mobile-Only Nav with Offset&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;4759a92f-4b27-4854-bb2c-299854634e93&#8243; sticky_offset_top=&#8221;127px&#8221; global_module=&#8221;45704&#8243; saved_tabs=&#8221;all&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_row _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; width=&#8221;90%&#8221; custom_margin=&#8221;0px||||false|false&#8221; custom_padding=&#8221;0px||||false|false&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;4_4&#8243; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_code admin_label=&#8221;Eureka Mobile Nav &#8211; Select Dropdown&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; custom_css_free_form=&#8221;select {||||      font-size: 1em; \/* Adjust font size *\/||      padding: 10px;   \/* Optional: Increase padding for better spacing *\/||      width: 100%;||      box-sizing: border-box;\/* Optional: Adjust width to fit the container *\/||      height: 50px;||}||||    \/* Style for dropdown options (fallback if needed) *\/||select option {||      font-size: 1.2em; \/* Ensures option text matches select styling *\/||      width: 100%;||    }&#8221; global_colors_info=&#8221;{}&#8221;]<select name=\"dropdown\" onchange=\"location = this.value;\"><!-- [et_pb_line_break_holder] --><option value=\"\">Solinst Eureka Menu<\/option><!-- [et_pb_line_break_holder] --><option value=\"https:\/\/www.solinst.com\/instruments\/solinst-eureka\/\">Solinst Eureka Main Page<\/option><!-- [et_pb_line_break_holder] -->  <!-- [et_pb_line_break_holder] --><option value=\"https:\/\/www.solinst.com\/instruments\/solinst-eureka\/quote\/\">Get a Quote<\/option><!-- [et_pb_line_break_holder] --><option value=\"https:\/\/www.solinst.com\/instruments\/solinst-eureka\/contact\/\">Contact Us<\/option><!-- [et_pb_line_break_holder] --><option value=\"https:\/\/www.solinst.com\/instruments\/solinst-eureka\/distributors\/\">Solinst Eureka Distributors<\/option><!-- [et_pb_line_break_holder] -->  <!-- [et_pb_line_break_holder] --><\/select>[\/et_pb_code][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=&#8221;1&#8243; specialty=&#8221;on&#8221; _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;5a5bca26-a9a5-4e6c-8fca-d64da3bdcd40&#8243; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;1_4&#8243; _builder_version=&#8221;4.16&#8243; custom_padding=&#8221;|||&#8221; global_colors_info=&#8221;{}&#8221; custom_padding__hover=&#8221;|||&#8221;][et_pb_menu menu_id=&#8221;252&#8243; admin_label=&#8221;Eureka Main Nav&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;242faa89-ac4f-4e46-90fe-505e8c1eab79&#8243; global_module=&#8221;45700&#8243; saved_tabs=&#8221;all&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_menu][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; custom_margin=&#8221;10px||||false|false&#8221; global_module=&#8221;46733&#8243; saved_tabs=&#8221;all&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<p><a href=\"https:\/\/solinst.com\/eureka\" title=\"Solinst Eureka\"><strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/01\/solinst-eureka-logo-800w.webp\" width=\"271\" height=\"49\" alt=\"solinst eureka logo\" class=\"wp-image-44307 alignnone size-full\" \/><\/strong><\/a><\/p>\n<p><strong>Solinst Eureka<\/strong><br \/>2113 Wells Branch Pkwy, Suite 4400<br \/>Austin, TX, USA<br \/>78728<\/p>\n<p>Tel: +1 512-302-4333<br \/>Fax: +1 512-251-6842<br \/>email: <a href=\"mailto:eureka@solinst.com\">eureka@solinst.com<\/a><\/p>\n<p>[\/et_pb_text][et_pb_slider disabled_on=&#8221;on|on|off&#8221; 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button_bg_color=&#8221;#f58025&#8243; button_border_width=&#8221;2px&#8221; button_border_radius=&#8221;20px&#8221; button_font=&#8221;|600|||||||&#8221; global_colors_info=&#8221;{}&#8221; sticky_transition=&#8221;on&#8221;]<\/p>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<h2><strong><\/strong><\/h2>\n<p><strong><\/strong><\/p>\n<p><strong><\/strong><\/p>\n<p><strong><\/strong><\/p>\n<p><strong><\/strong><\/p>\n<p><strong><\/strong><\/p>\n<h2><strong>Water Quality Probes<\/strong><\/h2>\n<p>Solinst Eureka, a global leader in the design and manufacture of multiparameter water quality sondes.<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>[\/et_pb_slide][\/et_pb_slider][et_pb_slider disabled_on=&#8221;on|on|off&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; link_option_url=&#8221;https:\/\/www.solinst.com\/field-services\/?utm_source=solinst&#038;utm_medium=WC-global-sidebar-position2&#038;utm_campaign=FS-field-services&#8221; global_module=&#8221;53561&#8243; saved_tabs=&#8221;all&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_slide button_text=&#8221;Learn More&#8221; button_link=&#8221;https:\/\/www.solinst.com\/en-gb\/field-services\/?utm_source=solinst&amp;utm_medium=WC-global-sidebar-position2&amp;utm_campaign=FS-field-services&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; background_color=&#8221;RGBA(255,255,255,0)&#8221; background_enable_color=&#8221;on&#8221; background_image=&#8221;https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/02\/solinst-field-services-sidebar.webp&#8221; background_enable_image=&#8221;on&#8221; custom_button=&#8221;on&#8221; button_bg_color=&#8221;#f58025&#8243; button_border_width=&#8221;2px&#8221; button_border_radius=&#8221;20px&#8221; button_font=&#8221;|600|||||||&#8221; global_colors_info=&#8221;{}&#8221; sticky_transition=&#8221;on&#8221;]<\/p>\n<h2><strong>Solinst Field Services<\/strong><\/h2>\n<p><strong><\/strong><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p><span>Safeguard your project\u2019s success and mitigate any potential for downtime or additional costs.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>[\/et_pb_slide][\/et_pb_slider][\/et_pb_column][et_pb_column type=&#8221;3_4&#8243; specialty_columns=&#8221;3&#8243; _builder_version=&#8221;4.16&#8243; custom_padding=&#8221;|||&#8221; global_colors_info=&#8221;{}&#8221; custom_padding__hover=&#8221;|||&#8221;][et_pb_row_inner column_structure=&#8221;1_2,1_2&#8243; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;3676f7e6-7b83-4698-94ce-2cc9fa9ae43d&#8221; custom_padding=&#8221;0px||||false|false&#8221; hover_enabled=&#8221;0&#8243; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;][et_pb_column_inner type=&#8221;1_2&#8243; saved_specialty_column_type=&#8221;3_4&#8243; _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;default&#8221; background_color=&#8221;RGBA(255,255,255,0)&#8221; custom_padding=&#8221;|||0px|false|false&#8221; custom_css_free_form=&#8221;width: 68%!important;||margin-right: 2%!important;&#8221; global_colors_info=&#8221;{}&#8221; background__hover_enabled=&#8221;on|hover&#8221; background_color__hover=&#8221;&#8221; background_enable_color__hover=&#8221;off&#8221;][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; header_2_font_size=&#8221;24px&#8221; width=&#8221;100%&#8221; hover_enabled=&#8221;0&#8243; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<h2><strong>Why measure pH?<\/strong><\/h2>\n<p>pH is a measurement of water\u2019s acidity or alkalinity. Water with a pH less than seven is acidic; water with a pH greater than seven is alkaline (basic). The pH of water is determined by dissolved, pH-active salts. For instance, dissolving sodium hydroxide in pure water will increase the pH because the hydroxide ion is a pH-active base, and dissolving hydrogen sulfide in pure water will decrease the pH because the hydrogen ion is a pH-active acid. However, dissolving sodium chloride in water will not change the pH because neither sodium nor chloride is a pH-active ion.    <\/p>\n<p>The pH of water determines the form of dissolved, pH-active salts. Suppose, for instance, that an ammonia-based fertiliser flows into a river via rainfall runoff. If the pH of the river is below nine, most of the ammonia species present will be in the form of ammonia, NH3. If the river pH is above pH nine, most of the ammonia species present is in the form of ammonium, NH4+. This is important because ammonia is toxic to biota, whereas ammonium can be a nutrient for biota.    <\/p>\n<p>pH also determines the solubility of metals in the water. Metals like iron and chromium are more soluble at low pH, and so more available for uptake by fish and other biota. At high pH, the metals are less soluble, and more likely to be bound into sediment than available for biota.  <\/p>\n<p>Changes in long-term pH trends can signal the need for more detailed chemical study of the water and its contamination sources.<\/p>\n<p>&nbsp;<\/p>\n<h2><strong>How is pH measured?<\/strong><\/h2>\n<p>pH is measured with a pH sensor and reference electrode. The pH sensor is a small, glass bulb filled with an electrolyte of known pH. If the pH of the sample water is different from that of the electrolyte, a voltage is created across the glass bulb. That voltage changes predictably with the pH of the sample water and is measured through the reference electrode. The reference electrode contains an electrolyte separated from the sample water not by a glass bulb, but by a micro-porous material, often Teflon, which allows the electrolyte to contact the water without being quickly diluted by the water.   <\/p>\n<p>There are two types of reference electrodes found in water-quality instruments. The first employs a small volume of high viscosity, \u201cgelled\u201d electrolyte. The gelled-electrolyte reference electrodes do not require periodic replacement of the electrolyte. However, they must be replaced approximately once a year or more often because the user cannot replace the electrolyte.   <\/p>\n<p>The second type of reference electrode employs a large volume of low-viscosity (un-gelled) electrolyte. The resulting \u201cflowing-junction\u201d typically establishes a more stable measurement than do gelled-electrolyte reference electrodes, especially as the gelled electrolyte ages. The flowing-junction electrolyte requires new electrolyte every two months or so. However, refilling the electrolyte means that you do not have to replace the entire reference electrode (as you do with gelled-electrolyte models).   <\/p>\n<p>The reference electrode used for pH measurement can simultaneously facilitate measurements with ORP electrodes and ion-selective electrodes (ISEs).<\/p>\n<p>pH sensors are ordinarily calibrated with commercially available standards, called pH buffers. You can choose two- or three-point pH calibration. Two-point calibrations use a seven (neutral) buffer and a second buffer whose value is near that of the waters you intend to monitor, normally a four buffer (acidic), or a ten (basic). If you are measuring in waters whose pH might range significantly above and below seven, you can increase your measurement accuracy slightly with a three-point calibration using seven, four, and ten buffers.[\/et_pb_text][\/et_pb_column_inner][et_pb_column_inner type=&#8221;1_2&#8243; saved_specialty_column_type=&#8221;3_4&#8243; _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;default&#8221; background_color=&#8221;RGBA(255,255,255,0)&#8221; custom_css_free_form=&#8221;width: 30%!important;&#8221; global_colors_info=&#8221;{}&#8221; background_color__hover=&#8221;&#8221; background__hover_enabled=&#8221;on|hover&#8221; background_enable_color__hover=&#8221;off&#8221;][et_pb_image src=&#8221;https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/01\/solinst-eureka-ph-sensor.webp&#8221; alt=&#8221;solinst eureka ph sensor&#8221; title_text=&#8221;Solinst Eureka pH Sensor&#8221; align=&#8221;center&#8221; align_tablet=&#8221;center&#8221; align_phone=&#8221;center&#8221; align_last_edited=&#8221;on|tablet&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; custom_margin_tablet=&#8221;20px||||false|false&#8221; custom_margin_phone=&#8221;20px||||false|false&#8221; custom_margin_last_edited=&#8221;on|tablet&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_image][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; header_2_font=&#8221;|700|||||||&#8221; header_2_text_color=&#8221;#000000&#8243; custom_margin=&#8221;27px||||false|false&#8221; header_2_font_size_tablet=&#8221;24px&#8221; header_2_font_size_phone=&#8221;24px&#8221; header_2_font_size_last_edited=&#8221;on|tablet&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<h2 style=\"text-align: left;\"><strong>pH Sensor for<br \/>Water Quality Sondes<\/strong><\/h2>\n<div class=\"jqw1mt QfrfFD cell\">\n<div dir=\"ltr\">\n<ul data-hook=\"stacked-info-section\" class=\"wEn8Wy\">\n<li class=\"De1MzN gZunol\" data-hook=\"stacked-info-item\"><strong>Range<\/strong><br \/>0 to 14 pH units<\/li>\n<li class=\"De1MzN gZunol\" data-hook=\"stacked-info-item\"><strong>Accuracy<\/strong><br \/>Accuracy \u00b10.1 within 10 \u00b0C of calibration; 0.2 otherwise<\/li>\n<li class=\"De1MzN gZunol\" data-hook=\"stacked-info-item\"><strong>Resolution<\/strong><br \/>0.01<\/li>\n<li class=\"De1MzN gZunol\" data-hook=\"stacked-info-item\"><strong>Units<\/strong><br \/>pH units<\/li>\n<li class=\"De1MzN gZunol\" data-hook=\"stacked-info-item\"><strong>Calibration<\/strong><br \/>pH buffers &#8211; two required, three points optionally<\/li>\n<li class=\"De1MzN gZunol\" data-hook=\"stacked-info-item\"><strong>Maintenance<\/strong><br \/>cleaning and calibration<br \/>refilling of the reference electrode<\/li>\n<li class=\"De1MzN gZunol\" data-hook=\"stacked-info-item\"><strong>Sensor Life<\/strong><br \/>6+ years<\/li>\n<li class=\"De1MzN gZunol\" data-hook=\"stacked-info-item\"><strong>Sensor Type<\/strong><br \/>glass pH sensor; Ag-AgCl refillable, flowing-junction<br \/>reference electrode<\/li>\n<\/ul>\n<h2><strong>Solinst Eureka\u2019s pH sensor<\/strong><\/h2>\n<p>Solinst Eureka\u2019s pH electrode with free-flowing junction reference electrode, is easy to maintain and simple to refill. A few pence and a few minutes every month or two to refill the <a href=\"https:\/\/www.solinst.com\/en-gb\/products\/solinst-eureka\/\" title=\"Solinst Eureka Water Quality Probes\"><strong>Solinst Eureka<\/strong><\/a> style reference electrode saves you money each year, and assures more stable readings. The refillable reference electrode is less susceptible to errors in low-conductivity waters, unlike gelled electrolyte used by other manufacturers.  <\/p>\n<\/div>\n<\/div>\n<p>[\/et_pb_text][et_pb_button button_url=&#8221;@ET-DC@eyJkeW5hbWljIjp0cnVlLCJjb250ZW50IjoicG9zdF9saW5rX3VybF9wYWdlIiwic2V0dGluZ3MiOnsicG9zdF9pZCI6IjQ1ODA3In19@&#8221; button_text=&#8221;Get Quote&#8221; admin_label=&#8221;get quote button&#8221; _builder_version=&#8221;4.27.4&#8243; _dynamic_attributes=&#8221;button_url&#8221; _module_preset=&#8221;c9e00792-1360-4998-8cf9-5f6772c944ba&#8221; global_module=&#8221;46404&#8243; saved_tabs=&#8221;all&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_button][\/et_pb_column_inner][\/et_pb_row_inner][et_pb_row_inner _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;3676f7e6-7b83-4698-94ce-2cc9fa9ae43d&#8221; hover_enabled=&#8221;0&#8243; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;][et_pb_column_inner saved_specialty_column_type=&#8221;3_4&#8243; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<h2><strong>What should I know about pH measurement in the field?<\/strong><\/h2>\n<p>pH sensors are sensitive to changes in temperature, but most instruments automatically compensate for temperature effects. pH accuracy is usually stated as +\/- 0.1 pH units, but this can change during extended field deployments.  <\/p>\n<p>With proper maintenance and calibration, you can expect good performance from a pH sensor in the field for several weeks or more. If you notice that the pH readings take more than a minute or so to stabilise, or if the pH readings are erratic, you may need to clean the pH sensor and\/or replace the reference electrolyte (if you have a refillable reference electrode). <\/p>\n<p>In low ionic-strength waters, i.e. those with conductivity less than about 200 \u00b5S\/cm, the flowing-junction reference electrode is superior to the gelled-electrolyte reference electrode because it is more successful in preventing \u201cjunction potentials\u201d that can bias the pH reading lower by up to one pH unit or more. A partially depleted, gelled-electrolyte reference electrode can calibrate easily in standard pH buffers (which have high ionic strengths) but cause undetectable errors in the field. The best way to avoid this problem is using a freshly refilled, flowing-junction reference electrode and checking pH calibration with a low ionic-strength buffer.  <\/p>\n<p>[\/et_pb_text][\/et_pb_column_inner][\/et_pb_row_inner][et_pb_row_inner _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; custom_padding=&#8221;||9px|||&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column_inner saved_specialty_column_type=&#8221;3_4&#8243; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<h2><strong>Related Products<\/strong><\/h2>\n<p>[\/et_pb_text][\/et_pb_column_inner][\/et_pb_row_inner][et_pb_row_inner column_structure=&#8221;1_2,1_2&#8243; disabled_on=&#8221;off|off|off&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; custom_margin=&#8221;0px||1em||false|false&#8221; custom_padding=&#8221;0px||0px||false|false&#8221; border_width_bottom=&#8221;1px&#8221; border_color_bottom=&#8221;#d3d3d3&#8243; global_module=&#8221;69009&#8243; saved_tabs=&#8221;all&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column_inner type=&#8221;1_2&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_image src=&#8221;https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/01\/solinst-eureka-multi-parameter-probes.webp&#8221; alt=&#8221;solinst eureka multi-parameter water probes&#8221; title_text=&#8221;Solinst Eureka Multi-parameter Water Probes&#8221; url=&#8221;@ET-DC@eyJkeW5hbWljIjp0cnVlLCJjb250ZW50IjoicG9zdF9saW5rX3VybF9wYWdlIiwic2V0dGluZ3MiOnsicG9zdF9pZCI6IjY1MDM3In19@&#8221; _builder_version=&#8221;4.27.4&#8243; _dynamic_attributes=&#8221;url&#8221; _module_preset=&#8221;default&#8221; border_color_all=&#8221;#bcbcbc&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_image][\/et_pb_column_inner][et_pb_column_inner type=&#8221;1_2&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; header_2_line_height=&#8221;1.3em&#8221; custom_margin=&#8221;60px||||false|false&#8221; custom_margin_tablet=&#8221;0px||||false|false&#8221; custom_margin_phone=&#8221;0px||||false|false&#8221; custom_margin_last_edited=&#8221;on|desktop&#8221; link_option_url=&#8221;https:\/\/www.solinst.com\/products\/level-measurement-devices\/103-tag-line\/&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<h3><a href=\"https:\/\/www.solinst.com\/instruments\/solinst-eureka\/water-quality-sondes\/manta-plumultiparameter-probes\/\" title=\"Manta Series Water Quality Probes\">Manta Series Water Quality Probes<\/a><\/h3>\n<p><a href=\"https:\/\/www.solinst.com\/en-gb\/products\/solinst-eureka\/\" title=\"Solinst Eureka Water Quality Probes\"><strong>Solinst Eureka<\/strong><\/a><span>  offers the largest selection of water quality sensor technologies in the industry. So in addition to standard configurations, each probe may be customised for your specific application. Pick sensors of your choice to fully populate larger probes, or add a battery pack to convert a probe to a logging device.  <\/span><\/p>\n<p>[\/et_pb_text][et_pb_button button_url=&#8221;@ET-DC@eyJkeW5hbWljIjp0cnVlLCJjb250ZW50IjoicG9zdF9saW5rX3VybF9wYWdlIiwic2V0dGluZ3MiOnsicG9zdF9pZCI6IjY1MDM3In19@&#8221; button_text=&#8221;Manta Water Quality Sondes&#8221; button_alignment=&#8221;left&#8221; button_alignment_tablet=&#8221;center&#8221; button_alignment_phone=&#8221;center&#8221; button_alignment_last_edited=&#8221;on|phone&#8221; _builder_version=&#8221;4.27.4&#8243; _dynamic_attributes=&#8221;button_url&#8221; _module_preset=&#8221;default&#8221; custom_button=&#8221;on&#8221; button_text_size=&#8221;18px&#8221; button_text_color=&#8221;#000000&#8243; button_bg_color=&#8221;#FFFFFF&#8221; button_border_color=&#8221;#ff8500&#8243; button_border_radius=&#8221;20px&#8221; button_icon=&#8221;&#x3d;||divi||400&#8243; custom_padding=&#8221;0px|||||&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_button][\/et_pb_column_inner][\/et_pb_row_inner][et_pb_row_inner column_structure=&#8221;1_2,1_2&#8243; disabled_on=&#8221;off|off|off&#8221; _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;default&#8221; border_width_bottom=&#8221;1px&#8221; border_color_bottom=&#8221;#d3d3d3&#8243; global_module=&#8221;69010&#8243; saved_tabs=&#8221;all&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column_inner type=&#8221;1_2&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_image src=&#8221;https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/03\/5001-trimeter-water-quality-sonde-965&#215;500-1.webp&#8221; alt=&#8221;solinst eureka trimeter water quality sondes&#8221; title_text=&#8221;Solinst Eureka Trimeter Water Quality Sondes&#8221; url=&#8221;@ET-DC@eyJkeW5hbWljIjp0cnVlLCJjb250ZW50IjoicG9zdF9saW5rX3VybF9wYWdlIiwic2V0dGluZ3MiOnsicG9zdF9pZCI6IjY0OTQwIn19@&#8221; _builder_version=&#8221;4.27.4&#8243; _dynamic_attributes=&#8221;url&#8221; _module_preset=&#8221;default&#8221; border_color_all=&#8221;#bcbcbc&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_image][\/et_pb_column_inner][et_pb_column_inner type=&#8221;1_2&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; header_2_line_height=&#8221;1.3em&#8221; custom_margin=&#8221;60px||||false|false&#8221; custom_margin_tablet=&#8221;0px||||false|false&#8221; custom_margin_phone=&#8221;0px||||false|false&#8221; custom_margin_last_edited=&#8221;on|desktop&#8221; link_option_url=&#8221;https:\/\/www.solinst.com\/products\/level-measurement-devices\/103-tag-line\/&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<h3><a href=\"https:\/\/www.solinst.com\/en-gb\/products\/solinst-eureka\/water-quality-sondes\/trimeter\/\" title=\"Manta Trimeter Water Quality Probe\">Manta Trimeter Water Quality Probe<\/a><\/h3>\n<p><span>The <a href=\"https:\/\/www.solinst.com\/en-gb\/products\/solinst-eureka\/water-quality-sondes\/trimeter\/\" title=\"Trimeter Low Cost Water Quality Sonde\"><strong>Trimeter<\/strong><\/a> holds any one sensor* from the Sensor Parameters list, plus temperature and depth sensors (both are optional). For example, a Trimeter configuration could be turbidity, temperature, and depth. Another example could be DO and temperature.  <\/span><\/p>\n<p>[\/et_pb_text][et_pb_button button_url=&#8221;@ET-DC@eyJkeW5hbWljIjp0cnVlLCJjb250ZW50IjoicG9zdF9saW5rX3VybF9wYWdlIiwic2V0dGluZ3MiOnsicG9zdF9pZCI6IjY0OTQwIn19@&#8221; button_text=&#8221;Manta Trimeter Water Quality Probe&#8221; button_alignment=&#8221;left&#8221; button_alignment_tablet=&#8221;center&#8221; button_alignment_phone=&#8221;center&#8221; button_alignment_last_edited=&#8221;on|phone&#8221; _builder_version=&#8221;4.27.4&#8243; _dynamic_attributes=&#8221;button_url&#8221; _module_preset=&#8221;default&#8221; custom_button=&#8221;on&#8221; button_text_size=&#8221;18px&#8221; button_text_color=&#8221;#000000&#8243; button_bg_color=&#8221;#FFFFFF&#8221; button_border_color=&#8221;#ff8500&#8243; button_border_radius=&#8221;20px&#8221; button_icon=&#8221;&#x3d;||divi||400&#8243; custom_padding=&#8221;0px|||||&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_button][\/et_pb_column_inner][\/et_pb_row_inner][et_pb_row_inner column_structure=&#8221;1_2,1_2&#8243; disabled_on=&#8221;off|off|off&#8221; _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;default&#8221; border_width_bottom=&#8221;1px&#8221; border_color_bottom=&#8221;#d3d3d3&#8243; global_module=&#8221;69121&#8243; saved_tabs=&#8221;all&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column_inner type=&#8221;1_2&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_image src=&#8221;https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/03\/5001-easyprobe-water-quality-sondes.webp&#8221; alt=&#8221;solinst eureka easyprobe water quality sondes&#8221; title_text=&#8221;Solinst Eureka EasyProbe Water Quality Sondes&#8221; url=&#8221;@ET-DC@eyJkeW5hbWljIjp0cnVlLCJjb250ZW50IjoicG9zdF9saW5rX3VybF9wYWdlIiwic2V0dGluZ3MiOnsicG9zdF9pZCI6IjY1MTQ3In19@&#8221; _builder_version=&#8221;4.27.4&#8243; _dynamic_attributes=&#8221;url&#8221; _module_preset=&#8221;default&#8221; border_color_all=&#8221;#bcbcbc&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_image][\/et_pb_column_inner][et_pb_column_inner type=&#8221;1_2&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; header_2_line_height=&#8221;1.3em&#8221; custom_margin=&#8221;60px||||false|false&#8221; custom_margin_tablet=&#8221;0px||||false|false&#8221; custom_margin_phone=&#8221;0px||||false|false&#8221; custom_margin_last_edited=&#8221;on|desktop&#8221; link_option_url=&#8221;https:\/\/www.solinst.com\/products\/level-measurement-devices\/103-tag-line\/&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<h3><a href=\"https:\/\/www.solinst.com\/en-gb\/products\/solinst-eureka\/water-quality-sondes\/easyprobe-water-quality-sonde\/\" title=\"EasyProbe: Water Quality Sondes\">EasyProbe: Water Quality Sondes<\/a><\/h3>\n<p><span>The <a href=\"https:\/\/www.solinst.com\/en-gb\/products\/solinst-eureka\/water-quality-sondes\/easyprobe-water-quality-sonde\/\" title=\"EasyProbe Water Quality Sonde\"><strong>EasyProbe<\/strong><\/a>, by Solinst Eureka, is a high-performance, cost-effective water quality monitor. It&#8217;s ideal for spot-checking, remote telemetry, education, research, aquaculture, and more. The EasyProbe20 includes sensors for temperature, dissolved oxygen, conductivity, and pH, while the EasyProbe30 adds a turbidity sensor. Eureka multiprobes are known for their reliability, with a three-year warranty covering all sensors, and have the lowest maintenance costs in the industry.   <\/span><\/p>\n<p>[\/et_pb_text][et_pb_button button_url=&#8221;@ET-DC@eyJkeW5hbWljIjp0cnVlLCJjb250ZW50IjoicG9zdF9saW5rX3VybF9wYWdlIiwic2V0dGluZ3MiOnsicG9zdF9pZCI6IjY1MTQ3In19@&#8221; button_text=&#8221;Manta Easy Probe Water Quality Sondes&#8221; button_alignment=&#8221;left&#8221; button_alignment_tablet=&#8221;center&#8221; button_alignment_phone=&#8221;center&#8221; button_alignment_last_edited=&#8221;on|phone&#8221; _builder_version=&#8221;4.27.4&#8243; _dynamic_attributes=&#8221;button_url&#8221; _module_preset=&#8221;default&#8221; custom_button=&#8221;on&#8221; button_text_size=&#8221;18px&#8221; button_text_color=&#8221;#000000&#8243; button_bg_color=&#8221;#FFFFFF&#8221; button_border_color=&#8221;#ff8500&#8243; button_border_radius=&#8221;20px&#8221; button_icon=&#8221;&#x3d;||divi||400&#8243; custom_padding=&#8221;0px|||||&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_button][\/et_pb_column_inner][\/et_pb_row_inner][et_pb_row_inner column_structure=&#8221;1_2,1_2&#8243; disabled_on=&#8221;off|off|off&#8221; _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;default&#8221; border_width_bottom=&#8221;1px&#8221; border_color_bottom=&#8221;#d3d3d3&#8243; global_module=&#8221;44627&#8243; saved_tabs=&#8221;all&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column_inner type=&#8221;1_2&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_image src=&#8221;https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/01\/3001-levelogger-5-ltc.webp&#8221; alt=&#8221;solinst levelogger 5 ltc water level water temperature and water conductivity datalogger&#8221; title_text=&#8221;Solinst Levelogger 5 LTC Water Level Water Temperature And Water Conductivity Datalogger&#8221; url=&#8221;https:\/\/www.solinst.com\/products\/dataloggers-and-telemetry\/3001-levelogger-series\/ltc-levelogger\/&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; border_color_all=&#8221;#bcbcbc&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_image][\/et_pb_column_inner][et_pb_column_inner type=&#8221;1_2&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; header_2_line_height=&#8221;1.3em&#8221; custom_margin=&#8221;60px||||false|false&#8221; custom_margin_tablet=&#8221;0px||||false|false&#8221; custom_margin_phone=&#8221;0px||||false|false&#8221; custom_margin_last_edited=&#8221;on|desktop&#8221; link_option_url=&#8221;https:\/\/www.solinst.com\/products\/level-measurement-devices\/103-tag-line\/&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<h3>Water Level, Temperature &amp; Conductivity Datalogging<\/h3>\n<p>The <a href=\"https:\/\/www.solinst.com\/products\/dataloggers-and-telemetry\/3001-levelogger-series\/ltc-levelogger\/\" title=\"Levelogger 5 LTC Level Temperature and Conductivity Datalogger\"><strong>Levelogger 5 LTC<\/strong><\/a> measures and logs water level fluctuations, temperature and conductivity. It is programmed to record at intervals as often as 2 seconds. It includes an 8-year battery, memory for 100,000 sets of readings, and comes in 6 pressure ranges. A PFAS-free coating (inside and out) provides superior corrosion and abrasion resistance.   <\/p>\n<p>[\/et_pb_text][et_pb_button button_url=&#8221;https:\/\/www.solinst.com\/products\/dataloggers-and-telemetry\/3001-levelogger-series\/ltc-levelogger\/&#8221; button_text=&#8221;Versatile Conductivity Datalogger&#8221; button_alignment=&#8221;left&#8221; button_alignment_tablet=&#8221;center&#8221; button_alignment_phone=&#8221;center&#8221; button_alignment_last_edited=&#8221;on|phone&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; custom_button=&#8221;on&#8221; button_text_size=&#8221;18px&#8221; button_text_color=&#8221;#000000&#8243; button_bg_color=&#8221;#FFFFFF&#8221; button_border_color=&#8221;#ff8500&#8243; button_border_radius=&#8221;20px&#8221; button_icon=&#8221;&#x3d;||divi||400&#8243; custom_padding=&#8221;0px|||||&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_button][\/et_pb_column_inner][\/et_pb_row_inner][et_pb_row_inner column_structure=&#8221;1_2,1_2&#8243; disabled_on=&#8221;off|off|off&#8221; _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;default&#8221; border_width_bottom=&#8221;1px&#8221; border_color_bottom=&#8221;#d3d3d3&#8243; global_module=&#8221;44750&#8243; saved_tabs=&#8221;all&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column_inner type=&#8221;1_2&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_image src=&#8221;https:\/\/www.solinst.com\/wp-content\/uploads\/2025\/01\/107-tlc-meter.webp&#8221; alt=&#8221;solinst model 107 tlc meter for temperature and conductivity profiling&#8221; title_text=&#8221;Solinst Model 107 TLC Meter For Temperature And Conductivity Profiling&#8221; url=&#8221;https:\/\/www.solinst.com\/products\/level-measurement-devices\/107-tlc-meter\/&#8221; align=&#8221;center&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; max_width=&#8221;100%&#8221; border_color_all=&#8221;#bcbcbc&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_image][\/et_pb_column_inner][et_pb_column_inner type=&#8221;1_2&#8243; _builder_version=&#8221;4.25.0&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; header_2_line_height=&#8221;1.3em&#8221; custom_margin=&#8221;60px||||false|false&#8221; custom_margin_tablet=&#8221;0px||||false|false&#8221; custom_margin_phone=&#8221;0px||||false|false&#8221; custom_margin_last_edited=&#8221;on|desktop&#8221; link_option_url=&#8221;https:\/\/www.solinst.com\/products\/level-measurement-devices\/103-tag-line\/&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<h3>TLC Meter \u2013 Measure Accurate Temperature, Level &amp; Conductivity<\/h3>\n<p>A <a href=\"https:\/\/www.solinst.com\/products\/level-measurement-devices\/107-tlc-meter\/\" title=\"TLC Meter Water Temperature and Water Conductivity Profiling\"><strong>TLC Meter<\/strong><\/a> provides accurate, stable temperature and conductivity measurements, displayed on a convenient LCD display for easy reading. Static water level and depth of readings are read off Solinst flat tape, which is precisely laser-marked every mm or 1\/100 ft. 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**************\/<!-- [et_pb_line_break_holder] -->var s_code=s.t();if(s_code)document.write(s_code)\/\/--><\/script><!-- [et_pb_line_break_holder] --><script language=\"JavaScript\" type=\"text\/javascript\"><!--<!-- [et_pb_line_break_holder] -->if(navigator.appVersion.indexOf('MSIE')>=0)document.write(unescape('%3C')+'!-'+'-')<!-- [et_pb_line_break_holder] -->\/\/--><\/script><noscript><a href=\"https:\/\/www.omniture.com\" title=\"Web Analytics\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/solinst.d2.sc.omtrdc.net\/b\/ss\/solinst-prod\/1\/H.21--NS\/0\" height=\"1\" width=\"1\" border=\"0\" alt=\"\"><\/a><\/noscript><!--\/DO NOT REMOVE\/--><!-- [et_pb_line_break_holder] --><!-- End SiteCatalyst code version: H.21. -->[\/et_pb_code][\/et_pb_column][\/et_pb_row][\/et_pb_section]<\/p>\n","protected":false},"excerpt":{"rendered":"<p>pH Sensor: Water Quality Probe<div class=\"et_pb_module dsm_breadcrumbs dsm_breadcrumbs_0\">\n\t\t\t\t\n\t\t\t\t\n\t\t\t\t\n\t\t\t\t\n\t\t\t\t\n\t\t\t\t\n\t\t\t\t<div class=\"et_pb_module_inner\">\n\t\t\t\t\t<nav class=\"dsm_breadcrumbs_wrap\">\n\t\t\t\t<ul class=\"dsm_breadcrumbs\" itemscope itemtype=\"https:\/\/schema.org\/BreadcrumbList\">\t\t\t<li class=\"dsm_breadcrumbs_item dsm_home_item dsm_home_item_custom\" itemprop=\"itemListElement\" itemscope\n\t\t\titemtype=\"https:\/\/schema.org\/ListItem\">\n\t\t\t\t<a href=\"https:\/\/www.solinst.com\/en-gb\/\" itemprop=\"item\" target=\"\">\n\t\t\t\t\t<span class='dsm_home_text_wrapper'>\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"et-pb-icon dsm_home_icon\">\ue009<\/span>\n\t\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"dsm_home_text\" itemprop=\"name\">\n\t\t\t\t\t\t\t\tHome\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/span>\n\t\t\t\t<\/a>\n\t\t\t\t<meta itemprop=\"position\" content=\"1\" \/>\n\t\t\t<\/li>\n\n\t\t<li class=\"dsm_breadcrumbs_separator\"> <span class=\"et-pb-icon dsm_separator_icon\">5<\/span><\/li><\/ul>\n\t\t\t<\/nav>\n\t\t\t\t<\/div>\n\t\t\t<\/div> Solinst Eureka2113 Wells Branch Pkwy, Suite 4400Austin, TX, USA78728 Tel: +1 512-302-4333Fax: +1 512-251-6842email: eureka@solinst.com Water Quality Probes Solinst Eureka, a global leader in the design and manufacture of multiparameter water quality sondes. &nbsp; &nbsp; &nbsp; &nbsp;Solinst Field Services &nbsp; &nbsp; &nbsp; Safeguard your project\u2019s success and mitigate any potential for downtime or additional costs. &nbsp; &nbsp;Why measure pH? pH is a measurement of water\u2019s acidity or alkalinity. Water with a pH less than seven is acidic; water with a pH greater than seven is alkaline (basic). The pH of water is determined by dissolved, pH-active salts. For instance, dissolving sodium hydroxide in pure water will increase the pH because the hydroxide ion is a pH-active base, and dissolving hydrogen sulfide in pure water will decrease the pH because the hydrogen ion is a pH-active acid. However, dissolving sodium chloride in water will not change the pH because neither sodium nor chloride is a pH-active ion. The pH of water determines the form of dissolved, pH-active salts. Suppose, for instance, that an ammonia-based fertiliser flows into a river via rainfall runoff. If the pH of the river is below nine, [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":220580,"parent":220652,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_et_pb_use_builder":"on","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"folder":[297],"class_list":["post-220575","page","type-page","status-publish","has-post-thumbnail","hentry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v27.5 (Yoast SEO v27.5) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>pH Sensors: Water Quality Sensors<\/title>\n<meta name=\"description\" content=\"pH Sensors: Water Quality Sensors\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.solinst.com\/en-gb\/products\/solinst-eureka\/water-quality-sensors\/ph-sensors\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Solinst Eureka pH Sensors\" \/>\n<meta property=\"og:description\" content=\"Explore the importance of pH sensors in water quality testing. 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