The majority of us are compelled to fill our aquarium from the tap. Personally, I prefer to do so, instead of using pond water which might contain larvae of dragon-flies, or water beetles.
Numerous districts have various high quality water, and in this respect tough water isn’t great for plants or fish. Tough water could be improved by boiling, allowing to cool, and then drawing off from the top by using a piece of rubber tube as a siphon.
The lower portion of the water should be thrown away.
Clean rain water could be utilized should you filter it via fine muslin and add two level teaspoons of sea salt to make up for any deficiency of minerals. The water might turn out to be cloudy whenever you add the salt, but it soon becomes clear.
Tap water is chlorinated to disinfect it. High concentrations of chlorine are harmful to fish and it is safer to let tap water stand for a couple of days prior to using it-the chlorine will then have disappeared into the atmosphere.