The store sells reverse osmosis and de-ionized water. I'm thinking reverse osmosis would be best. What you you think? I'm not going to use it to fill the whole tank, but I'm going to mix it a little at a time.
My tap water's pH is >8.4, hardness is like 300, alkalinity is 240
What fish are you trying to keep? In any case if you're going to start using RO water, you'll want to make the change gradual so as to not shock your fish. Even once you've completely switched over, I would still include some of your tap water in your mix as RO water is going to essentially have zero hardness, which means it'll be lacking in essential minerals your fish (and plants, if you have them) need and will be prone to large pH swings. But yes, between those two options you definitely want the RO water rather than just plain DI (although sometimes they sell water that's both).
Well... do you have fish in the tank with that hard water already? If so, I agree with batman above but if not, why mix at all? Just go with the RO from the get go and use only that to fill the tank... and to do water changes.
Yeah, like I said, I'm not going to add it all at once, just a little at a time. And I'm still going to keep mostly tap water. Maybe I shouldn't because my fish have been doing fine.
Until you tell us the species of fish you have we can't offer much advice. If you have soft water fish, depending upon what they are, they may look OK now but be suffering internally and coming to an earlier demise than otherwise. On the other hand, if they are suited to your water they may be fine as is. There are several soft water fish that will do OK in harder water, and there are some that will not.
The rasbora, gourami and kuhli loach are soft water fish, the others are probalby fine.
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Tropical Fish Keeping
597.8K posts
83.7K members
Since 2006
forum community dedicated to tropical fish owners and enthusiasts. Come join the discussion about species,breeding, health, behavior, aquariums, adopting, care, classifieds, and more! Open to fish, plants and reptiles living in freshwater or saltwater environments.