Reconstituted RO water

[Joshua Boring]

I hear a lot of people mention reconstituting ro water.
Is there a standard procedure for doing this?
I have been mixing tap water with ro to add minerals back in. Is this the most common way?
I also read about a type of discus buffer. Would this be better than using tap water?

[RogueDiscus]

If your tap water doesn't have nitrates or other negatives, then yes, adding back a bit of tap is common. Always depends on what's in your tap. I think discus buffers are trying to add back some KH, carbonate, which helps stabilize pH, but that's often what's in hard tap water. I think all animals need some sodium, calcium, magnesium, and potassium, the basic electrolyte elements. But how much varies.

[Joshua Boring]

My tap has roughly 20 nitrates and a ph of 7.8 or so. This is why I started using ro with some tap mixed in. It has helped with lowering ph and obviously the nitrates.
I was just curious if there was another way besides adding those nitrates from my tap. Just trying to be as consistent as possible.
Thanks for the tips

[Willie]

I hasten to point out that discus grow in the Amazon, where the water is incredibly soft - which means it contains no dissolved minerals. I've raised discus suscessfully on 100% R/O water for four years when we ran into water quality problems due to new piping. Products like R/O Right have no proof that they do anything. If you taste it, it's mostly table salt.

Willie

[Joshua Boring]

Willie, is there a big risk as far as ph crashing doing 100% ro water? That’s basically eliminating kh and gh correct??

[Willie]

Willie, is there a big risk as far as ph crashing doing 100% ro water? That’s basically eliminating kh and gh correct??

Yes, that's a good point. I've not had a pH crash, even though I was only doing 100% once a week back then. However, I did not overstock my tank. If there is a concern, I'd do a 80/20 mix with tap water. Alternatively, stick some crush corals in the filter for buffering. Adding chemicals is, in my experience, a recipe for disaster.

A long time ago, I kept Heckels in 100% R/O water at pH 5 and did have a pH crash. None of the discus showed any symptoms, but the cories got toasted!

[LizStreithorst]

I've did the same as you for years without pH crashes. It shouldn't have worked, but it did.