Water Change question

[Matt]

Originally Posted by Chad

I've always had issues with nitrates creeping up on change water that I just let cycle. So now I mix on the spot but keep a 45 gallon drum of fresh RO water on the go and heated w/o a circulation pump.

The really fresh water is chemically "hot" and not a great addition to the tank... It should cure before use if at all possible.

I personally mix water as soon as I can after a water change, and keep it on hand. It saved my bacon twice when I had major tank failures. I don't test the water, but I can't figure out what would cause nitrates... There aren't (should not be) any ammonia sources (organics), and there shouldn't be any nitrifying bacteria.