Water test
The optimum water test for your freshwater aquarium - ask us, we'll help you
BB Handel has been specialising in aquariums with heart and mind for a long time. We support our customers with passion and a great deal of expertise and provide advice on any topic as required. Time and again we receive calls and e-mail messages from people who keep a freshwater aquarium asking about the right or optimum water test. It is common knowledge that a water test must be carried out at regular intervals and, most importantly, must provide reliable data. This is because standardised values of individual components are extremely important, if not vital, especially for keeping certain fish species!
You can rely on our aquarium water tests
We have designed our product range so that it only includes products from reputable manufacturers in order to guarantee reliability. Here you will find a water test that specialises in certain substances, such as chlorine, nitrate, copper, silicate or iron, as well as a complete set that is particularly suitable for advanced aquarium owners. We will be happy to advise you on the individual products and give you our personal recommendation based on our own experience. BB Handel is your competent partner when it comes to a water test for your freshwater aquarium.
Filter products

Average rating of 4.8 out of 5 stars
Sera Ammonium-Ammonia Test – Precise monitoring for safe aquarium water Ammonium and ammonia (NH4/NH3) mainly originate from fish waste and can convert into each other depending on the pH value. While ammonium is generally harmless, ammonia is toxic to fish and invertebrates. The Sera NH4/NH3 Test reliably determines the total concentration of both substances to optimize water parameters as needed. Effective analysis to prevent ammonia poisoning Precise measurement to detect critical levels early Included chart allows easy conversion of actual ammonia content based on pH value Easy to use, ideal for regular water checks Actions for elevated ammonia levels In acute cases: Quick neutralization with Sera toxivec (freshwater) or Sera pond toxivec (pond) Long-term solution: Biological support with Sera bio nitrivec (freshwater), Sera marin bio reefclear (marine) or Sera pond bio nitrivec (pond) Technical details Sufficient for approx. 60 tests, ideal for continuous water analysis Enables targeted adjustment of water parameters for stable conditions Suitable for freshwater and marine aquariums as well as ponds With the Sera Ammonium-Ammonia Test, aquarists get a reliable tool for monitoring water quality to protect their fish and invertebrates from harmful pollutants and ensure a stable, healthy aquarium.
Content: 0.045 Liters (€354.44 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera Aqua Test Box Marin – Comprehensive Water Analysis for Marine Aquariums The Sera Aqua Test Box Marin offers marine aquarists a complete testing solution to reliably check the most important water parameters. Regular measurements help to detect issues early before they become dangerous for fish, corals, and other marine life. Precise Monitoring of Key Water Values This comprehensive test box enables analysis of: pH value – Regulates water chemistry and promotes stable conditions Carbonate hardness (KH) – Essential for the water's buffering capacity Ammonium/Ammonia (NH4/NH3) – Checks for toxic nitrogen compounds Nitrite (NO2) and Nitrate (NO3) – Indicators of biological load and filter efficiency Phosphate (PO4) – Monitoring to prevent unwanted algae growth Copper (Cu) – Protects fish and invertebrates from toxic levels Calcium (Ca) – Important measurement for coral skeleton formation Advantages for Marine Aquarists Early problem detection to optimize water parameters Easy and precise to use, ideal for regular water checks Ensures stable water conditions and healthy coral growth Technical Details Comprehensive testing solution for marine aquariums Accurate analysis for targeted water maintenance Ideal for beginners and experienced aquarists With the Sera Aqua Test Box Marin, marine aquarists receive an effective tool for water analysis that ensures optimal aquarium conditions and guarantees long-term healthy habitats. Perfect for safe and precise water monitoring.

Average rating of 4.8 out of 5 stars
Sera Calcium Test – Precise measurement of calcium levels in marine aquariums A stable calcium level is essential for the growth and health of corals and invertebrates in marine aquariums. With the Sera Calcium Test, aquarists can quickly and reliably determine calcium levels and optimize the water accordingly. Precise analysis for optimal water parameters Measures up to 7,500 mg of calcium to detect fluctuations early Easy to use, ideal for regular water checks Supports the targeted adjustment of calcium levels for stable reef conditions Adjustment of calcium levels If Ca levels are too low, the addition of Sera marin COMPONENT 1 Ca is recommended If calcium levels are too high, a partial water change can help stabilize them Technical details Accurate test for marine aquariums Allows quick monitoring and adjustment of water parameters Ideal for long-term calcium management With the Sera Calcium Test, marine aquarists get a reliable tool to precisely measure calcium concentration and create optimal conditions for their corals. Perfect for stable and healthy marine aquariums.
Content: 0.015 Liters (€996.67 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera Chlorine Test – Precise determination of chlorine levels for fish-safe water The Sera Chlorine Test enables the quick and reliable determination of chlorine levels in aquarium water. Since even low concentrations of chlorine can be harmful to fish and invertebrates, regular monitoring is essential for healthy water quality. Effective analysis for pollutant control Precise measurement of chlorine content to detect critical levels early Ideal for freshwater aquariums and ponds Sufficient for approx. 45 tests, perfect for long-term monitoring Measures for chlorine removal If the chlorine level is too high, the following products offer an effective solution: Sera toxivec or Sera pond toxivec for immediate chlorine removal in freshwater Sera aquatan or Sera KOI PROTECT for water conditioning and creating fish-friendly conditions Technical details Accurate water analysis for pollutant control Quick application for safe water quality Supports long-term care of aquariums and ponds With the Sera Chlorine Test, aquarists have a reliable method for checking water values to ensure a stable and healthy aquarium. Perfect for regular pollutant control testing.
Content: 0.015 Liters (€730.00 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera CO₂ Reagent – Refill Pack for Precise CO₂ Control Reliable carbon dioxide measurement is essential for optimal water quality in the aquarium. The Sera CO₂ Reagent Refill Pack is specially developed for the Sera CO₂ Long-Term Test and ensures long-term precise monitoring of CO₂ levels. Advantages of the Sera CO₂ Reagent: Easy to use: Quick refilling of the reagent for continuous measurements. Precise CO₂ control: Supports stable CO₂ concentration for healthy plant growth. Long-lasting effect: Guarantees reliable results for optimal water quality. Perfect complement to the Sera CO₂ Long-Term Test: For ongoing monitoring and adjustment of CO₂ supply. Optimal water care: In combination with the Sera CO₂ Long-Term Test, the refill pack provides an efficient solution for precise CO₂ measurement, allowing aquarists to optimally supply their aquatic plants. With the Sera CO₂ Reagent Refill Pack, CO₂ control remains reliable and precise – for a healthy and balanced aquarium system.
Content: 0.015 Liters (€596.67 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera Copper Test – Precise monitoring for safe aquarium water Copper (Cu) is highly toxic to invertebrates such as shrimp and crabs and can also trigger sensitive reactions in fish. The Sera Copper Test allows for the quick and reliable determination of copper levels in aquarium water to avoid risks for aquarium inhabitants. Effective analysis for pollutant control Precise measurement of copper levels to detect critical values early Ideal for freshwater and marine aquariums to ensure optimal water conditions Sufficient for approx. 50 tests, perfect for regular monitoring Causes and solutions for elevated copper levels Medications and algae treatments can increase copper concentrations For elevated values, Sera aquatan offers a quick solution for the removal of copper from aquarium water Technical details Accurate water test for long-term healthy water parameters Supports a safe environment for fish and invertebrates Easy to use for precise results With the Sera Copper Test, aquarists get a reliable tool for monitoring water quality to protect ornamental fish and invertebrates from toxic copper exposure and ensure a stable, healthy aquarium.
Content: 0.015 Liters (€1,063.33 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera Cuvette Replacement Set – Precise measuring cuvettes for accurate water analysis The Sera Cuvette Replacement Set offers high-quality glass cuvettes specially developed for the precise execution of Sera water tests and the exact dosing of care and medicinal products. Thanks to their high-precision scale, they ensure reliable measurement results that meet the standards of a professional-grade measuring cuvette. Versatile applications Ideal for all Sera water tests to determine accurate water values Perfect for precise dosing of aquarium care products and medications High-quality glass material for maximum durability and accuracy Technical details Durable glass cuvettes with a long service life Precise scale for accurate measurements Replacement set for aquarists who value reliable water analysis With the Sera Cuvette Replacement Set, aquarists receive a high-quality and precise solution for accurately measuring water parameters and properly dosing care products – an essential accessory for professional aquarium maintenance.
Content: 3 piece/unit (€2.32 / 1 piece/unit)

Average rating of 4.8 out of 5 stars
Sera Iron Test – Precise monitoring for optimal plant nutrition The Sera Iron Test allows for quick and reliable determination of iron content (Fe) in aquarium water. Iron is an essential nutrient for strong plant growth, and a deficiency can lead to pale leaves and growth problems. Effective analysis for healthy aquatic plants Precise measurement of iron content to detect deficiencies early Detection of chelated (stabilized) iron for accurate water value assessment Easy to use, ideal for regular monitoring Targeted fertilization measures In case of iron deficiency, Sera florena or Sera florenette provide immediate nutrient supply Targeted adjustment of water parameters to promote optimal plant growth Technical details Sufficient for approx. 75 tests, perfect for long-term water analysis Enables precise monitoring and targeted optimization of plant nutrients Ideal for freshwater aquariums with demanding aquatic plants With the Sera Iron Test, aquarists have a reliable way to accurately determine the iron level and optimally adjust plant nutrition – for vigorous growth and a healthy, green underwater landscape.
Content: 0.015 Liters (€1,063.33 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera KH Test – Precise control of carbonate hardness for stable water values An optimal carbonate hardness level (KH) is essential for the stability of the pH value and the health of all aquarium inhabitants. The Sera KH Test allows reliable measurement of carbonate hardness to optimize the water and maintain a stable biological balance. Effective analysis for healthy water values Precise measurement up to 390 °dKH to detect critical fluctuations early Easy to use, ideal for regular water quality checks Suitable for freshwater and marine aquariums as well as ponds Measures to adjust carbonate hardness For low KH values, use Sera KH/pH-plus (fresh and marine water) or Sera pond bio balance (pond) For high KH values, filtration with Sera super peat (freshwater aquarium) helps to reduce them effectively Technical details Reliable water analysis for stable environmental conditions Supports long-term monitoring of water chemistry Essential for pH regulation and the health of aquarium life With the Sera KH Test, aquarists get a precise tool to determine carbonate hardness and adjust water quality – for a stable and healthy aquarium environment.
Content: 0.015 Liters (€596.67 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera Nitrate Test – Precise analysis for optimal water quality An increased nitrate level (NO3) is an indicator of high organic pollution in the aquarium. With the Sera Nitrate Test, aquarists can quickly and reliably determine the nitrate level and take targeted measures to improve water quality. Effective monitoring of nitrate levels Detects nitrate accumulation early, which can lead to algae problems Easy to use, ideal for regular water checks Enables targeted measures to improve water quality Measures to reduce nitrate levels Immediate solution: A partial water change reduces nitrate concentration in the short term Long-term optimization: Filtration with Sera Siporax Professional helps to permanently prevent nitrate buildup Technical details Sufficient for approx. 60 tests Precise and reliable analysis of water parameters Ideal for long-term water quality control in freshwater and marine aquariums With the Sera Nitrate Test, aquarists receive a reliable tool to precisely measure nitrate levels and keep the water sustainably clean and healthy.
Content: 0.015 Liters (€996.67 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera Nitrite Test – Reliable monitoring for healthy water values Nitrite (NO2) is among the most dangerous fish toxins in the aquarium and can accumulate in the water with insufficient biological filtration. The Sera Nitrite Test allows the quick and safe determination of nitrite levels to take targeted countermeasures and optimize water quality. Effective analysis to prevent nitrite poisoning Precise measurement to detect critical nitrite levels early Suitable for freshwater and marine aquariums as well as ponds Easy to use, ideal for regular monitoring Measures for elevated nitrite levels Slightly elevated values: Use Sera bio nitrivec (freshwater), Sera marin bio reefclear (marine) or Sera pond bio nitrivec (pond) for biological filtration support High nitrite load: Sera toxivec (freshwater) or Sera pond toxivec (pond) for rapid nitrite neutralization Technical details Sufficient for approx. 75 tests, perfect for long-term water analysis Supports stable water quality and healthy aquarium inhabitants Important monitoring tool for a safe aquarium environment With the Sera Nitrite Test, aquarists get a reliable method to determine nitrite levels and ensure a stable, safe and healthy aquarium. Perfect to prevent nitrite poisoning and long-term water issues.
Content: 0.015 Liters (€863.33 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera pH Test – Precise monitoring for stable water parameters A balanced pH level is essential for the health of fish, plants, and microorganisms in the aquarium. The Sera pH Test allows aquarists to reliably determine the pH value and optimize the water to ensure stable conditions. Effective analysis for optimal water quality Precise measurement to detect pH fluctuations early Suitable for freshwater and marine aquariums as well as ponds Easy to use, perfect for regular monitoring Measures for pH adjustment Low pH levels can be corrected with Sera KH/pH-plus (fresh and marine water) or Sera pond bio balance (pond) High pH levels can be regulated with Sera pH-minus or filtration using Sera super peat Technical details Reliable water analysis for stable environmental conditions Enables targeted pH adjustment for healthy aquarium life Ideal for long-term water quality monitoring With the Sera pH Test, aquarists get a reliable tool to precisely measure pH and ensure optimal water conditions – essential for a stable and healthy aquarium environment.
Content: 0.015 Liters (€596.67 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera Phosphate Test – Precise control for an algae-free aquarium An elevated phosphate level (PO4) can lead to unwanted algae growth and disrupt the balance in the aquarium. With the Sera Phosphate Test, the phosphate content can be quickly and reliably determined to take targeted measures for water optimization. Effective analysis for stable water quality Precise measurement to detect problematic phosphate levels early Easy to use, ideal for regular checks in freshwater, marine aquariums, and ponds Enables targeted measures to reduce phosphate accumulations Measures to reduce phosphate levels Excess phosphate can be easily removed with the following products: Sera phosvec for freshwater Sera phosvec Granules for freshwater and marine water Sera pond phosvec for ponds Technical details Sufficient for approx. 60 tests, ideal for long-term water analysis Ensures algae-free water conditions and a stable ecosystem Perfect for freshwater and marine aquariums as well as garden ponds With the Sera Phosphate Test, aquarists have a reliable tool to precisely measure phosphate levels and keep the aquarium clean and healthy in the long term. An essential aid to prevent algae problems.
Content: 0.015 Liters (€1,063.33 / 1 Liters)

Average rating of 4.8 out of 5 stars
Sera Quick Test – Quick water analysis for optimal aquarium values The Sera Quick Test enables a fast and easy check of the most important water parameters in the aquarium. With just one test strip, you can reliably check pH, carbonate hardness, total hardness, nitrate, and nitrite. Effective routine check for healthy water Easy to use: Dip the test strip into the water for one second Fast results: Compare with the scale on the packaging after 1 minute Ideal for beginners and experienced aquarists Precise diagnosis and optimization Deviations from optimal water values can be precisely determined using Sera drop tests Supports the targeted adjustment of water chemistry for long-term stable conditions Technical details Test strips for analyzing five important water parameters Safe and reliable method for freshwater and marine aquariums Perfect for regular checks to prevent water problems With the Sera Quick Test, aquarists get an effective solution to quickly check their water values and ensure a stable, healthy aquarium.
Content: 50 piece/unit (€0.38 / 1 piece/unit)

Average rating of 4.8 out of 5 stars
Sera Silicate Test – Precise monitoring to reduce diatom growth An increased silicate level (SiO3) can promote the growth of diatoms in marine and freshwater aquariums and impair water quality. With the Sera Silicate Test, the silicate content can be quickly and reliably determined to take targeted measures to improve water conditions. Effective analysis for healthy water values Easy to use, ideal for regular monitoring Precise measurement to detect problematic silicate concentrations early Suitable for marine and freshwater aquariums Measures to reduce silicate levels Silicate levels above 1 mg/l should be effectively bound with Sera marin silicate clear Continuous monitoring of silicate levels helps stabilize the biological balance Technical details Quick and precise water analysis for stable water quality Enables targeted action against diatom growth Perfect for marine and freshwater aquariums With the Sera Silicate Test, aquarists get a reliable tool to accurately determine silicate levels and keep the aquarium free of algae in the long term. An essential solution for a stable and healthy aquarium environment.
Content: 0.045 Liters (€398.89 / 1 Liters)
























































































































































