Updated: Apr 5, 2019
Water quality is the most important aspect in keeping a healthy and thriving fish tank. There are many species that can adapt to a large range of water parameters. However there are also some very delicate species like Discus. A lot of water that comes from faucets in homes are not always the best. Depending on if you have city water or well water, it can greatly change. So if the water you have at your disposal isn’t proper, then what is your options? On one hand a lot of fish supply stores have water available. But if you have a large tank that would be a very expensive route along the road. The other option is using an reverse osmosis (RO) system.
Reverse osmosis is the process of filtering water. To put it simply, the water is passed through a lot of tight films. This will purify the water, removing all the tiny impurities. The water that is left is absolutely pure water. Some people just use this water, however that isn’t a smart move. Since the water is pure, it has a neutral pH. But it also has no gH. What gH does is it stabilizes the pH. Having a low gH, means that the pH of the water is more susceptible to changing. If the pH swings, that can be fatal for the fish. So it is important that after the water is purified, you add a remineralizer. Adding this will help give the proper minerals that makes the water safe for your fish tank.
You can purchase RO systems quite easily online or at many fish stores. The price on these will vary depending on how many gallons they can filter in a day. I use one that can filter 50 gallons a day and that is good enough for maintaining my 45 gallon community tank.