Aquarium Water Sources
With so many things to consider, the quality of water that you put in your fish tank is the basic if not the most important thing to keep in mind. You can choose from a few different sources.
The easiest and most readily available way to fill your tanks with water is to turn on the tap; and if you’re sourcing it from the municipal water source, it should be disinfected and free from most bacteria. However, some tap water may still contain small amounts of harmful elements that can harm your fish, like chlorine which is toxic to fish and can lead to respiratory difficulty and asphyxiation(the state or process of being deprived of oxygen, which can result in unconsciousness or death)
Unlike tap water, well water does not go through any treatment, and is simply piped directly into your faucets. The quality of well water also depends on your location. It may be free from chlorine, but not from other harmful elements like phosphates and nitrates, which are not favorable for your fish.
So you may think bottled water is the ideal water for your fish since it is highly marketed as safe and healthy for humans, and therefore must be good for fish, right? Well, maybe not exactly. In fact, some bottled water still contains high levels of chlorine, which, again, harms your fish. Besides, using bottled water to regularly fill your tank is significantly more expensive, especially if you keep a large fish tank at home.
Well, rainwater is probably the cheapest source of water for your fish tanks. It’s absolutely free, only that, you can only use it during the rainy season. And though it may come free, rainwater tend to have low mineral content and varying pH. It is more likely to be polluted by chemical exhausts from nearby factories, smoke and motor emissions from the city, and more.
Although distilled water is free from most contaminants, it is stripped of almost 99.99% of minerals including calcium and magnesium which are beneficial to your fish. If you’re using distilled water, you will need to remineralize it before filling your tank. And just like bottled water, it is significantly expensive to use.
Reverse Osmosis (RO) Water
Reverse osmosis may be excellent in filtering contaminants including minerals, chlorine and some large bacteria. However, it may not be as effective against smaller bacteria. If you are using RO water, you will need to remineralize it also before filling your tank.
Deionized (DI) Water
Like RO and distilled water, deionized water, still needs to be remineralized before using. Deionization may not be as effective in removing bateria, but it is able to filter mineral and chemical contaminants that even RO cannot filter.