Pick fish for your water

Pick fish for your water. Select fish who are native to waters having a similar chemical properties (pH and GH) to your local tap water. If you have hard water, choose hard water fish. If you have soft water, choose soft water fish. This is especially important if you water is outside the 6.5-7.5 pH range. Changing the natural hardness (or pH) of your tap water can be hard work and often takes the fun out of keeping aquariums. Moreover, bungled attempts at adjustment are common and often worse for fish than the original sub-optimal water conditions. A good way to learn which fish live happily in your local water is to check with a local fish store.