RO or DI usage in FW

[JoeMomma]

I know that RO is good for saltwater, but you usually add either kalk or salt (with CA and pH boosters in it) to the RO.

As far as freshwater goes, is the water too "bland" to support plants and fish correctly? If you use CO2, won't your pH drop dangerously?

And, assuming RO isn't good, what should you use? Tapwater will likely lead to algae problems, wont it?

[Devilishturtles]

Tapwater will not lead to algae problems, and most tap water is what everbody uses for their tanks. It is not too bland as you put it to support plants and fish. Granted if you live in the city or use a municipal water supply, a dechlorinator is neccessary, but cost only 1-3 dollars depending on the brand.

I mix RO/DI water into my FW tank only to lower the hardness, and most use it only because they have bad tap water, such as I do. RO/DI water is just water...nothing is in it, so in essence it is bad for the fish and plants, becaues that is what they need to live....that is what the helpful bacteria need to grow, an so on. People who use RO/DI water also use an additive that puts all of this beneficial stuff into the water. So, to answer you question, tapwater is perfect for most FW tanks, but the little things all depend on what type of fish you have. Most never deal with RO/DI water at all.

I hope this answers your question...

[JoeMomma]

Thanks a lot! You answered my question perfectly.

[loganj]

You can, if your tap water is extremely bad, use RO/DI water in conjunction with a product such as RO Right. This will bring the mineral content of the water up depending on how you mix it. I would only go this route with VERY delicate fish or really bad tap water though. You might want to add a drinking water kit to your RO unit though and use it for that...the water tastes really great.