RO DI Water vs Tap Water-
Has this ever happened to you?
You start up your dream aquarium which happens to be saltwater. You research and get it ready to fill up. You look into an RO/DI unit but decide its not worth the money, I mean water is water right? So you buy some inexpensive salt and get the garden hose to fill er up. Now she looks beautiful right? A few months go by and you find that you have a bad algae problem and you start periodically losing fish. What is going on and how did this dream aquarium turn into a nightmare??
This is perhaps on of the biggest mistakes people make when starting a saltwater aquarium. Years and years ago we used tap water for our salt setups and we know what can happen.
What is RO/DI water anyway?
This stands for Reverse Osmosis Deionized Water- Simply put its water that has had everything taken out of it, called total dissolved solids (TDS).
What makes it better then getting water from my hose?
There are a few factors that make RO/DI water the better option:
When you have RO/DI water you start with pure water, its so pure in fact that we shouldn’t drink straight RO/DI water. We need some type of minerals in the water or it will hurt our teeth. This isn’t an issue for saltwater aquariums because you add some type of salt mix into the water. If you use it to top off your aquarium, it wont be to pure because you are adding it to already salted water.
When you use water from your faucet, whether its well water or city water, there are things in there that don’t belong in your aquarium. In Well water there are minerals and such that probably are not in the ocean. This can hurt your salty animals. In city water we can only imagine what chemicals are in that water.
Are there downsides to an RO/DI unit?
There is always something that you can find on the “not as good” side to virtually anything but you always hope that the good outweighs the bad. When you are making RO/DI water at home the downside is that you waste some water. Another downside is cost.
Is there an alternative?
There are many local fish stores who make and sell RO/DI water by the gallon. This is a good alternative if you are not ready to dive into making it at home yet, or if you have a smaller tank and don’t want to buy a unit until you upgrade to a bigger aquarium.
What happens if I started with tap water?
If you started with tap water and you are having problems then you might want to consider doing water changes and your top offs with RO/DI water from now on. It could take a while to get the aquarium back but you have to be patient and your consistency will pay off. Remember that even if you don’t see a problem now, it could creep up on you years later due to the porosity of live rock sucking in everything then possibly leeching it out later. (check out our live rock blog for more info on that.)
Let us know in the comments if you have experience with one vs the other type of water.