Perhaps the most important aspect in successfully keeping either a freshwater or marine aquarium is good water quality.

Maintaining optimum water quality will help you keep everything healthy and happy and make your aquarium a beautiful and exciting addition to your home.
In order to ensure this, it is vital, though, that all of the main water parameters are regularly monitored as a means of evaluating water conditions and to provide an indication of any action needed to be taken.

Test kits like those from the Hagen Nutrafin range have made it easy to measure aquarium water conditions over a whole range of the main basic water parameters. These user-friendly tests have easy to follow instructions that allow precise measurements to be made quickly and accurately. Advice is also provided on evaluating the results and clear and concise suggested courses of action offered for each result.

These kits are well designed to ensure high levels of accuracy using pharmaceutical grade bottle droppers to give precise measured amounts of reagent and glass test tubes that don't discolour over time (like plastic tubes) guarantee accurate test results are maintained after multiple use.

pH is a very important basic parameter that is easily measured with a Nutrafin test kit and is a good indicator of general water conditions.

pH is an abbreviation of potential hydrogen and determines whether water is acidic, neutral or alkaline. The scale of pH is 0 - 14 which defines neutral as 7.0, with acidic levels under 7.0 and alkaline over 7.0. As pH plays an important role in the blood systems of aquatic organisms it is recommended that water is tested weekly at different times in order to chart any changes that could affect the well-being of aquarium inhabitants. Nutrafin pH test kits are offered in wide range form (4.5 9.0) for fresh and salt water use, a high range kit (7.4 8.6) again for both fresh and salt water use and a low range (6.0 7.6) kit especially for use in fresh water to monitor pH levels for Tetras, Discus, Angels and other fish groups requiring acid conditions.
pH also gives a general indication of high levels of organics in the water as this is accompanied usually by a sudden dip in pH values.

Levels of Ammonia (NH3/NH4), Nitrite (N02) and Nitrate (N03) are, however, much more accurate indicators of organic pollution and biological activity (Nitrogen Cycle).

Ammonia is highly toxic in its un-ionised form (NH3) and weekly testing of ammonia levels will indicate whether the biological filter is coping okay or if ammonia is reaching dangerous levels.

Testing Nitrite levels tracks the progression of biological activity a stage further. Like Ammonia, Nitrite is highly toxic - a sudden spike in nitrite usually signals a dangerous imbalance in the system. Weekly testing of nitrite levels is also important therefore to ensure biological activity is at safe levels.

Nitrate, the final stage in the break down of organic pollutants, accumulates over time and is difficult to remove by conventional filtration methods. Although much less toxic, nitrate still needs to be managed down to low levels to avoid stress related illness in fishes and over abundance of nuisance forms of algae.

Nutrafin test kits are available for Ammonia (0.0 6.1 mg/L), Nitrite (0.0 3.3 mg/L) and Nitrate (0.0 110.0 mg/L) all for use in fresh or salt water.

General Hardness (GH) and Carbonate Hardness (KH) are two important water parameters which provide a further means of managing water quality. General Hardness measures dissolved salts in the water, whilst Carbonate Hardness measures its capacity to neutralise acids (the buffering capacity).

Many fresh water fishes have definite preferences regarding acidity/alkaline levels some requiring acid conditions whilst others are more comfortable in alkaline water. It's strongly recommended that you research the needs of your fish as local tap water may necessitate the use of various types of filter media and water treatment products to help achieve stable, favourable conditions for these fish.

Similarly with marine aquarium subjects, such as corals, low levels of GH and KH can lead to poor health and growth. The GH/KH Nutrafin test kit measures General Hardness in fresh water and Carbonate Hardness in both fresh and salt water. A supplementary Nutrafin Calcium (Ca) test allows detailed measurement of the specific levels of calcium needed to maintain various marine invertebrates.

Phosphate levels tend to increase over time, often due to overfeeding but may also be found in water supplies. Regular monitoring coupled with water changes or the use of phosphate removers will avoid high levels of phosphate occurring, which can contribute significantly to unsightly algae.

Phosphate is usually found in aquarium water as orthophosphate (HP04 and P04) and the Nutrafin phosphate test kit determines levels of these phosphates (0.0 5.0 mg/L) in fresh or salt water.

Iron levels also need to be carefully monitored as iron deficiencies in fresh water planted aquariums can prevent lush growth. In natural ocean water, on the other hand, levels of iron are on average around 0.0001 mg/L and it's necessary in marine aquariums to ensure iron does not reach a detectable reading.

The Nutrafin Iron test for fresh and salt water is an invaluable tool in water management terms and can also help distinguish between safe chelated iron (which is more easily assimilated by plants) and toxic non-chelated iron.

Nutrafin test kits are available singly or in a full Master Test Kit, which contains all of the tests mentioned. A Mini Master Test Kit is another alternative for fresh water fish enthusiasts which provides all you need for routine weekly water testing of pH, wide range, Ammonia, Nitrite and Nitrate in ready-to-use format.

Re-published from the FBAS Bulletin by kind permission of the author

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Last updated March 2005

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