Using Tapwater Conditioners

A variety of tapwater conditioners are available from aquarium shops. These often perform a number of useful functions, including: Removing chlorine, chloramine and heavy metals. Preventing marked shifts in pH value in fresh water. Protecting delicate and/or damaged tissues.

These benefits can be of great importance when dealing with recently imported and/or damaged fish, and some proprietary tapwater conditioners have been developed to enhance the effects of certain disease treatments. However, the activity of certain disease treatments, particularly copper-based ones, may be reduced in the presence of some tapwater conditioners.


Where any doubt exists, seek the manufacturer's advice. Where necessary, the active ingredients of most tapwater conditioners can be removed by filtration over activated carbon and/or making partial water changes with unconditioned water. If tapwater conditioners are likely to reduce the efficiency of a disease treatment, all new water may be "conditioned" using one or more of the following methods: By filtration over activated carbon. By vigorous aeration for 12 hours. By using sodium thiosulphate (1-2 drops of 10 percent solution per 10 litres of water is usually sufficient).

While these methods do not have all the benefits of a good quality tapwater conditioner, each will remove chlorine and generally render the water safe for fish without interfering with any treatment. Under normal circumstances, however, be sure to treat all new water with proprietary conditioner before aquarium use.