algae changes On the Mathematics of aquarium water changes On the Mathematics of aquarium water changes chemistry algicides Substances used to kill algae in the aquarium. ammonia The most dangerous chemical naturally found in aquaria chlorine Ascorbic acid is the safest and cheapest way to neutralize chlorine and chloramine. cyanide Cyanide occurring in freshwater ferts Aquatic plant fertilizers hardness Water hardness history History of aquarium chemistry nitrates Hobby test kits are not accurate, and nitrates may not be as harmful as people believe. ph Acidity and alkalinity schreckstoff "Fright" substance selenium

rain Rain Water Rain water is the purest form of water known, although maybe not so much in a city where smoke and industrial waste clouds the issue, although after it rains for a while, it is a lot cleaner. Similarly, when collecting rainwater from downspouts, it's best to let the rain wash them for an hour or so before collecting water. More elaborate systems can be plumbed in with large storage tanks, proper runoff and drainage which can then be plumbed into the house for any non-potable water source. If one branch is diverted to have an additional UV filter as well as a carbon filter then it would indeed be potable. temperature