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Water Quality Answers


Is soft water safe for tropical fish?

Yes, soft water is satisfactory for most tropical fish. According to several authorities, both fully soft water and municipally softened water would have no undesirable or toxic effect for use in an aquarium.

When making the change from hard to soft water, it is necessary to make the substitution on a gradual stepwise basis of new water for old. This follows the basic pattern in regard to any change in the environment for tropical fish. This applies to temperature, pH of water, food, as well as to hardness. Drastic changes, of course, would constitute a shock to the delicate systems of such fish and would result in fatalities. Preferably replace about one-fourth of the aquarium water at weekly intervals with soft water. Eventually, the aquarium will have a supply consisting of essentially soft water, and the fish will suffer no ill effects as a result of the change.

Note: While soft water is an improvement in that it reduces the clouding and scaling of the glass panels of an aquarium, it does not of itself necessarily provide a suitable environment for the breeding of tropical fish. Authorities indicate that water of low dissolved solids and pH control my be more desirable for breeding, though this depends on the species. Since total dissolved solids content of a softened water is the same as that of the untreated raw water, a supply with a lower dissolved solids content must be gained in some other way. Blending of softened water with reverse osmosis or distilled water may produce the conditions conducive to breeding.

Wednesday,February 23, 2000 at 11:48 AM