What is the GH
(general hardness), KH
(carbonate hardness) and pH of your water supply?
This information can usually be obtained from your water supply company's website or by telephoning them. If they can't help you, take a glass full of tap water to the local pet shop and get them to test it for you. Write the results down (in numbers) when they do the tests. And ask them what the results are in (eg: ppm
, dGH, or something else).
Depending on what the GH
of your water is, will determine what fish you should keep.
Angelfish, discus, most tetras, most barbs, Bettas, gouramis, rasbora, Corydoras and small species of suckermouth catfish all occur in soft water (GH
below 150ppm) and a pH below 7.0.
Livebearers (guppies, platies, swordtails, mollies), rainbowfish and goldfish occur in medium hard water with a GH
around 200-250ppm and a pH above 7.0.
If you have very hard water (GH
above 300ppm) then look at African Rift Lake cichlids, or use distilled or reverse osmosis water to reduce the GH
and keep fishes from softer water.
Danios, loaches and plecos should not be kept with African Rift Lake cichlids. they come from completely different water and the cichlids regularly attack and kill these fish.
You can soften water with a reverse osmosis unit but these can waste a lot of water in the process. You can make a solar still out of a plastic storage container and a bucket. You can buy distilled water or reverse osmosis water but this can get pricey.
As for water softeners, try not to use them for soft water fishes because the sodium that replaces the calcium damages the kidneys in fish, birds and mammals, including people.