Water Quality

Maintain pristine water conditions with our complete range of water quality products. Healthy water is the foundation of a thriving aquarium, and our selection of treatments, conditioners, and testing supplies ensures your aquatic environment stays balanced and safe.

Why Water Quality Matters:

    • Prevents fish stress and disease
    • Supports beneficial bacteria growth
    • Promotes vibrant fish colors and health
    • Creates a stable, natural environment
    • Reduces maintenance issues

    Regular testing and proper water treatment are essential for long-term aquarium success. Find everything you need to keep your water parameters perfect.

    150 products

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    • Sale -10%Last stock! NT LABS Test Phosphate (PO4) NT LABS Test Phosphate (PO4)

      NT Labs NT LABS Test Phosphate (PO4)

      3 in stock

      NT Labs Test Phosphate (PO4) is an aquarium water testing kit used to measure phosphate (PO₄) levels in freshwater or marine tanks. What is phosphate?Phosphate is a naturally occurring compound that enters the aquarium through fish waste, uneaten food, and decaying organic matter. While small amounts of phosphate are normal, excessive phosphate levels can contribute to poor water quality, which results in unwanted algae growth. In reef aquariums, high phosphate levels may also inhibit coral growth and affect coral health. Phosphate is invisible to the naked eye, so regular testing is important to maintain a balanced and healthy aquarium environment. What is the recommended phosphate level?For freshwater aquariums, phosphate levels should generally be kept below 1.0 mg/L (ppm) to help control algae growth. For marine and reef aquariums, the ideal phosphate level remain below 0.03 – 0.1 mg/L (ppm), as corals and sensitive marine organisms require very low phosphate levels for optimal health. What do I do if the phosphate level is wrong?If phosphate levels are too high, perform partial water changes and reduce overfeeding or excess waste buildup in the aquarium. Cleaning the substrate and filter regularly can also help lower phosphate levels. Phosphate-removal media may help maintain lower phosphate levels, especially in reef aquariums. If phosphate levels remain consistently high, it is important to check feeding habits, source water quality, and overall aquarium maintenance routines. How to use? - Ensure the test tube is clean.- Take a 5 ml sample of water into the test tube.- Add the recommended number of drops of the Phosphate reagent.- Replace the test tube cap and shake thoroughly.- Wait the instructed development time, then compare the colour of the sample to the colour scale provided.- Lower phosphate levels are represented by lighter colours, while darker colours indicate higher phosphate concentrations.- Any colour forming after the recommended waiting time should be ignored.

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      3 in stock

      $14.41 $13.00

    • Sale -11%Last stock! NT LABS Test Nitrate (NO3) NT LABS Test Nitrate (NO3)

      NT Labs NT LABS Test Nitrate (NO3)

      3 in stock

      NT Labs Test Nitrate (NO3) is an aquarium water testing kit used to measure nitrate (NO₃) levels in freshwater or marine tanks. What is nitrate?Nitrate is produced as the final stage of the aquarium nitrogen cycle when beneficial bacteria break down nitrite. Unlike ammonia and nitrite, nitrate is far less toxic to fish, but prolonged exposure to high nitrate levels can cause stress, poor health, algae growth, and reduced vitality in fish and corals. Nitrate is invisible to the naked eye, so regular testing is important to maintain good water quality. What is the recommended nitrate level?For freshwater aquariums, nitrate should ideally be kept below 40 mg/L (ppm). Sensitive fish species may require even lower levels. In marine and reef aquariums, nitrate levels are generally recommended to remain below 10–20 mg/L (ppm), with reef systems often targeting very low nitrate levels for coral health. What do I do if the nitrate level is wrong?If nitrate levels become too high, perform a partial water change to dilute the nitrate concentration. Regular maintenance such as gravel cleaning, avoiding overfeeding, improving filtration, and increasing live plant growth can also help reduce nitrate levels. In marine aquariums, protein skimmers, refugiums, or nitrate-removal media may assist in maintaining low nitrate levels. How to use? - Ensure the test tube is clean.- Take a 5 ml sample of water into the test tube.- Add the recommended number of drops of Nitrate Reagent 1 and shake thoroughly.- Add the recommended number of drops of Nitrate Reagent 2 and shake again thoroughly.- Wait the instructed development time, then compare the colour of the sample to the colour scale provided.- A pale or colourless sample indicates low nitrate levels, while deeper colours indicate higher nitrate concentrations.- Any colour forming after the recommended waiting time should be ignored.

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      3 in stock

      $14.59 $13.00

    • Sale -10%Last stock! NT Labs Broad Range pH Test Kit (6-9) NT Labs Broad Range pH Test Kit (6-9)

      NT Labs NT Labs Broad Range pH Test Kit (6-9)

      3 in stock

      NT LABS Broad Range Test pH 6-9 What is pH?The new Broad Range pH Test is for testing water within the pH range of 6 – 9. This pH test now covers the pH range more likely observed in your aquarium and also offers improved precision with 0.5 unit determination. What is the correct pH level?There is no definitive correct pH as different fish species have their preferred pH range. Generally, the ideal pH value will lie between 7 and 8, but there are some exceptions. When purchasing fish from your local aquatic retailer, always enquire as to the specific water requirements of the fish you are buying. What do I do if the level is wrong?If you do need to adjust the pH of your aquarium, it is vital to do this slowly to not shock the fish. Change no more than 0.5 pH units per 2 days. Providing your tap water is of suitable pH, substantial water changes can correct a dangerous pH level. It is also important to check the KH of the aquarium. Use of pH adjusters, such as KH Up – pH Stabiliser will raise the pH caused by soft or aged water. For fish that live in soft, acid water use bogwood to gently lower the pH and soften the water. How to use? Ensure the test tube is clean. Take a 5ml sample of water into the test tube. Add 5 drops of the pH reagent; replace the test tube cap and shake thoroughly. Compare the colour of your sample to the colour scale provided. FAQ:Q: My pH reagent has changed colour, is it still ok to use?  A: Our pH reagent can change colour over time. It will start green, but can change to any colour on the colour chart. This is normal and you will still get accurate results.

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      3 in stock

      $14.41 $13.00

    • Sale -12%Last stock! JBL Proaqua Fe test kit (Measure Iron) JBL Proaqua Fe test kit (Measure Iron)

      JBL JBL Proaqua Fe test kit (Measure Iron)

      3 in stock

      Simple and reliable monitoring of the water values in aquariums/ponds. Determines the ideal iron value in fresh and marine water Laboratory comparator system to compensate the inherent water colour: fill plastic cuvette with sample water, add reagent to both cuvettes, place cuvettes in holder, read values off colour chart Use: 1 x after setting up a new aquarium, afterwards weekly. In case of green algae problems or when plants don’t grow properly You will find detailed information and troubleshooting tips about water analysis on the JBL website in Essentials/Aquarium or Pond Package contents: 1 iron quick test for approx. 50 measurements, incl. reagent, 2 glass vials with screw caps, syringe, comparator block and colour scale. Reagent refill separately available Healthy aquarium/healthy pond with conditions close to natureThe right water values are dependent on the fish stock and the plants in the aquarium/pond. Even if the water looks clear it can be contaminated. With bad values diseases or algae can appear in the aquarium/pond. To maintain a healthy aquarium/pond with conditions close to nature it is important to check and adapt the water values regularly.For each water analysis JBL provides water tests in the form of quick tests or colour change tests. These determine a certain value or several values in one go. With these water tests you can recognise algae problems and negative nitrate, nitrite, potassium, magnesium values etc. In addition to a sufficient CO2 supply, iron and trace elements are essential for water plants. Strongly growing aquatic plants permanently need iron and other trace elements, and these are only durable for a limited period during the coupling to so-called chelates, a common feature in modern fertiliser preparations (e.g. JBL Ferropol, JBL Fe +Microelements), so regular monitoring with the JBL Iron Test Fe is needed, along with repeated fertilisation if necessary. Pond owners should check their well water for iron before using it for their pond. Too high iron content can lead to problems in the pond.JBL Online LaboratoryRegular control for a healthy aquarium/pond with conditions close to nature. Enter your water values into the JBL Online Laboratory and get an in-depth analysis of your values within seconds. Recommended iron contents:Freshwater aquarium (community aquarium): 0.05-0.2 mg/lLake Malawi/Lake Tanganyika aquarium: 0.05-0.2 mg/lPlant aquarium with few fish (aquascaping): 0.1-0.5 mg/lMarine aquarium: 0.002-0.05 mg/lPond: 0.05-0.1 mg/l

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      3 in stock

      $29.67 $26.00

    • Sale -7% NT Labs Water Test Kit - Multi test/Mini test NT Labs Water Test Kit - Multi test/Mini test

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      NT Labs NT Labs Water Test Kit - Multi test/Mini test

      6 in stock

      NT LABS Aquarium Lab Multi Test Kit (6in1 test kit) Easy to Use Six Essential Tests for Freshwater Aquariums Accurate Liquid Drop Tests for Reliable Results - Much More Accurate Than Water Test Strips Includes a Water Quality Guide, Colour Charts, and an Integrated Test Tube Rack Up to 200 Tests (combined) The main factor in successful fish keeping and health lies in the maintenance of good water quality. Ammonia, nitrite and pH levels in the aquarium should be checked regularly. The Aquarium Lab Multi-Test Kit comprises up to 200 tests combined of the 6 key parameters to test in your aquarium: ammonia, nitrite, nitrate, pH, GH and KH. All the tests are liquid drop tests from a dropper bottle so all the drops are the same size. Full instructions are included detailing optimum levels and suggestions for correction, along with an integrated test tube rack. All you have to do is add your aquarium water to the test tube and count the drops needed. The back of the box details clear pictorial instructions so you can see what to do from the start.  This test kit reports concentration in terms of nitrogen (NH3-N), (NO2-N) or (NO3-N) to be compatible with reported safe concentrations as they apply to fish and plants. If you are interested in knowing the ionic concentration of the measured parameter, multiply your result by 1.21 (NH3-N), 3.29 (NO2-N), or 4.43 (NO3-N). NT LABS Aquarium Water Mini Test (3in1 test kit) When to use?The key to successful fish keeping is excellent water quality. The Aquarium Water Mini tests three water parameters: pH, Nitrite and Ammonia. Ammonia: What is ammonia?Ammonia is excreted by fish as a waste product. It is extremely toxic to fish, and is broken down into less toxic nitrite by the beneficial bacteria in the filter of your aquarium. Nitrite: What is nitrite?Nitrite is produced by the beneficial bacteria in the pond and filters as they break down harmful ammonia excreted by fish. Although not as toxic as ammonia, nitrite is still very damaging to the health of the fish. Nitrite itself is broken down into nitrate which is significantly less harmful to fish. pH: What is pH?pH is the measure of the acidity or alkalinity of the water in your aquarium.  The pH scale runs from 0 to 14. Very acid water is pH 0 and very alkaline water is pH 14. Neutral water that is neither acid nor alkaline is pH 7. How do I do the tests?A full instruction leaflet is included in the pack which talks you through each parameter, what it should be, and what you should do if the readings are incorrect. This test kit reports concentration in terms of nitrogen (NH3-N) or (NO2-N) to be compatible with reported safe concentrations as they apply to fish and plants. FAQ:Q: My pH reagent has changed colour, is it still ok to use? A: Our pH reagent can change colour over time. It will start green, but can change to any colour on the colour chart. This is normal and you will still get accurate results. “Comprehensive and easy to use, I often like to have a couple of bottles of Anti-Internal Bacteria treatment or Disease Solve to hand. Nice to know that I’m not the only one who rates these products!” Nathan Hill, the Associate Editor of Practical Fishkeeping Magazine

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      6 in stock

      $33.00 - $58.00

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    • Sale -7%Last stock! JBL ProAqua pH 3.0-10.0 test kit (Measure pH) JBL ProAqua pH 3.0-10.0 test kit (Measure pH)

      JBL JBL ProAqua pH 3.0-10.0 test kit (Measure pH)

      3 in stock

      Simple and reliable monitoring of the water values in ponds and aquariums. Determines the ideal pH value in fresh and marine water Quick test: fill plastic cuvette with sample water, add reagent, read value of the sample off colour chart When to use: for setting up a new aquarium: daily for one week, afterwards weekly You will find detailed information and troubleshooting tips about water analysis on the JBL website in Essentials/Aquarium or Pond Package contents: 1 complete kit with one reagent pH 3.0-10.0, 1 cuvette and 1 colour chart; contents for approx. 50 measurements Healthy aquarium/healthy pond with conditions close to natureThe right water values are dependent on the fish stock and the plants in the aquarium/pond. Even if the water looks clear it can be contaminated. With bad values diseases or algae can appear in the aquarium/pond. To maintain a healthy aquarium/pond with conditions close to nature it is important to check and adapt the water values regularly.For each water analysis JBL provides water tests in the form of quick tests or colour change tests. These determine a certain value or several values in one go. With these water tests you can recognise algae problems and negative nitrate, nitrite, potassium, magnesium values etc.Why test?The well-being of aquarium and pond dwellers and the healthy growth of aquatic plants depend to a large extent on the pH level being kept as constant as possible. The pH level can also affect many substances dissolved in the water. Fluctuations in the pH level are definitely to be avoided.JBL Online LaboratoryRegular control for a healthy aquarium/pond with conditions close to nature. Enter your water values into the JBL Online Laboratory and get an in-depth analysis of your values within seconds.Recommended pH values:Freshwater aquarium (community aquarium): 6.5-7.5Lake Malawi/Lake Tanganyika aquarium: 7.8-9.2Plant aquarium with few fish (aquascaping): 6.0-7.0Marine aquarium: 7.9-8.5Pond: 7.5-8.5

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      3 in stock

      $14.35 $13.40

    • Sale -11%Last stock! ANS PRO II CO2 Regulator Compact (Dual Stage with Solenoid) ANS PRO II CO2 Regulator Compact (Dual Stage with Solenoid)

      ANS ANS PRO II CO2 Regulator Compact (Dual Stage with Solenoid)

      3 in stock

      ANS Pro II Regulator - New generation Dual Stage Regulator with the improved material and technologyDual Stage Technology Adjustable working pressure from 0 – 70PSIFine tuning output controller for easy co2 output adjustmentStabilize Co2 outputPro II Compact Regulator Feature Compact Size for Small Cylinder and Space Saver Safe 12V DC Integrated Solenoid Valve Power adapter with universal voltage 100V-240V Integrated Solenoid Valve. Adjustable working pressure up to +/- 70PSI Fine tuning controller with bubble counter included. Singe gauge reading (working pressure) Thread : W21.8 standard for UK, Europe, Japan and Taiwan (Our Cylinder sold are all W21.8 ) Why Dual Stage? Dual Stage regulator help to reduce the pressure in the CO2 cylinder. This will help the following: Solenoid valves are unable to function properly with the high pressure in the Co2 bottles. Without Dual Stage, Co2 output will be unstable and may cause irregulator Co2 output amount. You will be able to use high quality diffuser

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      3 in stock

      $160.19 $142.00

    • Sale -10%Last stock! ANS PRO II CO2 Regulator Advance (Dual Stage with Solenoid) ANS PRO II CO2 Regulator Advance (Dual Stage with Solenoid)

      ANS ANS PRO II CO2 Regulator Advance (Dual Stage with Solenoid)

      3 in stock

      ANS Pro II Regulator - New generation Dual Stage Regulator with the improved material and technology Dual Stage Technology Adjustable working pressure from 0 – 70PSI Fine tuning output controller for easy co2 output adjustment Stabilize Co2 output Each ANS PRO II CO2 Extender Manifold can be added on the regulator to achieve 2 - 10 outlets. Pro II Co2 Advance Regulator Feature Safe 12V DC Integrated Solenoid Valve Power adapter with universal voltage 100V-240V Integrated Solenoid Valve. Adjustable working pressure up to +/- 70PSI Fine tuning controller with bubble counter included. Dual gauge reading (tank volume and working pressure) Thread : W21.8 standard for UK, Europe, Japan and Taiwan (Our Cylinder sold are all W21.8 ) Why Dual Stage? Dual Stage regulator help to reduce the pressure in the CO2 cylinder. This will help the following: Solenoid valves are unable to function properly with the high pressure in the Co2 bottles. Without Dual Stage, Co2 output will be unstable and may cause irregulator Co2 output amount. You will be able to use high quality diffuser

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      3 in stock

      $172.45 $155.00

    • Sale -9%Last stock! ISTA Intense Flow CO2 Bubble Counter

      ISTA ISTA Intense Flow CO2 Bubble Counter

      3 in stock

      The ISTA Intense Flow CO2 Bubble Counter is a CO2 bubble counter made by ISTA. It is a component for a CO2 system. The data provided does not include further details such as size, materials or fittings.

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      3 in stock

      $7.71 $7.00

    • Sale -9% EDEN 425 Aquarium Heater (Various Model) EDEN 425 Aquarium Heater (Various Model)

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      Oase EDEN 425 Aquarium Heater (Various Model)

      18 in stock

      Simple and easy to use Internal Aquarium Heater from Eden Eden is a brand from the prestigious Oase manufacturing group, well known for premium pond products.It provides accurate water temperature readings thanks to its thermostat system that reacts only to the water temperature and not to the heating element within the unit.For added control there is also the added ability to manually calibrate the thermostat should it be needed.The Eden heaters can be fully submersed in the water and can be safely attached to the sides of the tank with suction cups. Unlike traditional regulating heaters, the EDEN 425 regulating heater does not flow through the bimetal element and therefore does not experience any heating due to the Joule effect. Such heating causes the thermostat to switch on early in traditional control heaters before it could even measure the actual water temperature. Since the bimetal element is not traversed by the current, the thermostat of the control heater 425 always switches on the basis of the actually measured water temperature. A special, double contact, which is elastically attached to the bimetal, ensures a permanently reliable function. Another setting button, which is integrated into the main rotary control, enables the thermostat to be readjusted to adapt it to the operating conditions and to remove any slight deviations between the set temperature and the temperature determined by a separate precision thermometer. The EDEN 425 adjustable heater can be easily installed in the aquarium with the supplied bracket and ensures a constant temperature for a perfect ecosystem in the aquarium. Features: Precise heat control Accurate thermostat Fully Submersible An integrated control light clearly shows when heating Specifications - 25 watts Length x diameter: 205 x 33 mm Power: 25 watts Cable length: 1.5 meters Specifications - 50 watts Length x diameter: 205 x 33 mm Power: 50 watts Cable length: 1.5 meters Specifications - 100 watts Length x diameter: 243 x 33 mm Power: 100 watts Cable length: 1.5 meters Specifications - 150 watts Length x diameter: 315 x 33 mm Power: 150 watts Cable length: 1.5 meters Specifications - 200 watts Length x diameter: 315 x 33 mm Power: 200 watts Cable length: 1.5 meters Specifications - 300 watts Length x diameter: 370 x 33 mm Power: 300 watts Cable length: 1.5 meters

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      18 in stock

      $45.00 - $69.00

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    • Sale -7%Last stock! SALIFERT Ammonia Test kit for saltwater (NH4) SALIFERT Ammonia Test kit for saltwater (NH4)

      Salifert SALIFERT Ammonia Test kit for saltwater (NH4)

      3 in stock

      Product:Ammonia Test Profi Test is highly accurate and is designed for the saltwater aquarium.  Ammonia and Ammonium are substances which should be converted rapidly into Nitrite followed by Nitrate and Nitrogen gas. If this does not happen then the aquarium is not fully cycled or biological processes are not proceeding as they should. The Salifert Ammonia test is straightforward and measures the sum of toxic ammonia and ammonium in just a few minutes. The kit can perform approx. 50 measurements and can detect 0.5 ppm of total ammonia easily. Instructions: 1) Using the provided syringe(2ml), add 2ml of aquarium water into the test vial. 2) Using the provided syringe(1ml), add 0.5ml of NH3 reagent to the test vial and swirl for 30 seconds.  Add the remaining 0.5ml of NH3 reagent and swirl the test vial for another 10 seconds. 3) Allow to stand for 3 minutes. 4) Swirl the test vial for 5 seconds. 5) Place the test vial in front of the colour chart to match the colour of the solution. The values on the colour chart are in mg/L of total Ammonia (NH3 plus NH4+) Note:The use of protective gloves and eye protection is recommended. Please read the instructions carefully before using the product.  Salifert:Salifert is a Netherlands base company that produces top of the line test kits as well as tank additives and foods for marine and reef aquariums. Salifert is well established and popular with hobbyist for their accurate and affordable test kits. 

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      3 in stock

      $20.52 $19.00

    • Sale -5%Last stock! AQUAPRO Stainless Steel U-Pipe 6mm (for co2 or air tube) AQUAPRO Stainless Steel U-Pipe 6mm (for co2 or air tube)

      Aquapro AQUAPRO Stainless Steel U-Pipe 6mm (for co2 or air tube)

      3 in stock

      Upgrade your setup with the AQUAPRO 6mm Stainless Steel U-Pipe, engineered for durability, precision, and a clean, professional finish. Crafted from high-grade 304 stainless steel, this U-shaped pipe offers excellent resistance to corrosion and rust, making it ideal for long-term use in both indoor and outdoor applications. Key Features Premium 304 stainless steel construction Corrosion and rust resistant Durable matte finish for a modern look Secure barbed ends for tight, leak-resistant connections Precision 6mm sizing for consistent performance Easy to install and compatible with flexible tubing Dimensions Inner Width: 12.5mm Height (short side): 30mm Height (long side): 50mm Base Width: 23mm

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      3 in stock

      $7.36 $7.00

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