Water changes are often not understood properly. Newcomers into the hobby are strongly influenced by friends or forums, and its likely that they take their understanding of water changes as their own.
The act of water changing is not seen as scientific, when compared to other aspects of the hobby such as the injection of CO2, the measure of lighting intensity or the nitration process of filtration. However, water changing is the most important maintenance act that any aquarist can perform. In this article, we seek to provide the right approach to effective water change.
The changing of water in an aquarium accomplishes one key necessity, the physical removal of nitrate, a by product of the nitrification cycle that is not consumed by the filter’s colony of bacteria. If the aquarium is newly established and the filter is immature, then the changing of water will also remove ammonia and nitrite, which are poisonous to fauna in any quantity. Phosphate, algae, dirt, other impurities, organic materials and tannins (if you are using driftwood or leaves) are removed during a water change as well.
In the normal aquarium or planted aquarium, the frequency of water change is to be determined by the current water parameters. Aquarium test kits that detect ammonia, nitrite and nitrate are easily available in almost any local fish shops. Brands that we recommend are API and Sera, API being the most economical and Sera having the better test kit.
As a general guide line for a newly established aquarium, tests should be performed daily till ammonia and nitrite are undetectable, this will indicate that the nitrification cycle has been established and that the beneficial bacteria within the filter is healthy. Only at this stage, should fauna be added into the aquarium.
After the nitrification cycle has been established, testing for ammonia, nitrite and nitrate at regular intervals is greatly encouraged. The amount of flora, fauna and size of the filter’s bacteria colony will determine how often a water change will be required. When moderate nitrate is detected, a water change of about 30 t0 50 percent should be performed. This amount will sufficiently remove enough nitrate before it reaches an excessive and dangerous amount. In adverse situations where ammonia or nitrite are detected, a larger percentage of water changed may be needed to stablise water quality to safe parameters.
Experience have shown that a water change is usually needed on a weekly or fortnightly basis for the majority of aquariums. But for the minority of aquarists who keep monster fishes or unusual aquariums, this generalisation may differ greatly.
When adding fresh water to the aquarium, an anti chlorine solution should be added to chemically remove any chlorine or chloramine. Chlorine and chloramine are highly poisonous and fatal to any fauna, with death being a certainty over time.
Chlorine can naturally be sterilised by exposing it to a period of sunlight, or by removal using an active air stone for a few hours. Chloramine however, cannot be removed by these methods and only a chemical solution will be effective. We highly recommend Seachem Prime, an excellent water conditional that is the staple of many, removing not only chlorine and choramine, but detoxifying ammonia, nitrite and nitrate as well.
Determining the specific time for a water change should always be dependent on the testing of the aquarium’s water quality, and not by comparisons with other aquariums of similar capacity, maintenance habits or broad generalisations. Each aquarium is a mini aquatic ecosystem, unique in itself. Only be testing the aquarium regularly can the character of the aquarium be made known, making it possible for the aquarist to understand the aquarium and perform a water change just before water quality deteriorates.
It is important to perform a water change only when it is needed. Excessive water change will keep water quality pristine, however, the stressing of fauna is also highly likely. A water change is thus a delicate dance, all in the aquarium’s own tune, turning and stepping, just at the right moments.