Reverse osmosis questions

[catfishacr]

Hey, I'm moving soon and just found out my tap water has a PH of 9.25. I currently have south american fish ( Arowana, Lima cat, etc.) I'm not for sure but that ph seems too high for my fish. The house already has a culligans reverse osmosis unit.

I know nothing about RO units. Can someone fill me in on how reverse osmosis systems work and if I should use it? Also do i need to add minerals back to the water as well and if so can someone explain how to do that?

Thanks in advance.

 

[Gill Blue]

http://en.wikipedia.org/wiki/Reverse_osmosis
not straight RO water, but you can mix to get the right parameters.

 

[catfishacr]

When you say mix. Mix tap water with RO water and then find the parameters that I want?

 

[catfishacr]

One more question I just checked my KH and GH. Kh 4-5 and GH 5-6. Will mixing my tap water with RO water lower my KH too low? Ive read that you always want your KH above 4?