I'm using RO water in both my tanks...all fish are very healthy...running both for a little over a week...see here for more info on that:
http://www.fishlore.com/fishforum/fr...-question.html
At the moment (right now) both tanks are reading 0 Ammonia...20 ppg (mg/L) Nitrates.....the large tank is running about 3.0 ppg (mg/L) on Nitrites and the small one about 2.0 ppg (mg/L) on Nitrites...did a 20% water change last Friday.
Now I have read that because I use only RO water...that I should be using Aquarium Salt both for the health of the fish and to keep the Nitrites under control.
What are your views on this...the nitrite levels aren't freaking me out just yet.....but I have a slight twitch in my left eye....if you get my drift...LOL