tankman2

Could someone please explain to me what water hardness means. I plan to keep african cichlids and they require hard water. What does this mean and how do I know if I have hard or soft water?

Thanks

Isabella

By "hard water" two things can be meant. One is a pH that is high (say, around 8.0 in freshwater aquaria), and the other is water's "buffering capacity". Water that has good buffering capacity has a constant pH - be it low or high pH. Water that has poor buffering capacity may have pH swings - which isn't a good thing for any fish. So, always, it's best to have water with a good buffering capacity. You can check pH with a pH test, and you can check water's buffering capacity with tests for General Hardness (GH) and Temporary Hardness (KH). General Hardness is often referred to as "constant" or "unchanging", while Temporary Hardness, as the name suggests, changes and is also referred to as "Carbonate Hardness".

If you want to keep Cichlids that require higher pH, you'll have to create conditions of water that will be both high in pH and high in buffering capacity (so that the pH stays constant and doesn't jump up and down). I've never kept such Cichlids so I can't help you with how to set up and maintain such a tank. Though I think calcerous rocks and gravels can be used in such a setup to improve water's buffering capacity. But wait for someone knowledgeable to confirm this.

ncje

With africans I have always used a mixed substrate of small pebbles and shell grit. This keeps your water buffered pretty well, you may also consider sandstone rocks for caves, it also helps. People often talk about adding salt and I have found with soft water fish, previuosly a discus breeder and now angels salt is not needed at all. But my africans bred and showed beautiful color whn I added about one teaspoon of pure rocksalt for about every ten litres on watr changes. Pure rocksalt is cheap to buy. If you set up like I have mentioned there is no need for the expensive rift lake salt additives you see in stores.