Might be a bit of a basic question but how do you prepare your water?

My local water has chlorine (according to my water report)
I have a RO unit so for some time I've been drawing off water for w/cs by T'ing off the line between the filters and the RO membrane. The filters are a basic poly filter, a block carbon and a final filter which is supposed to remove Chlorine & Chloramine. I fill a water barrel then pre-heat it and keep it circulating with a small powerhead ready for my next w/c.
I read elsewhere (and I can't remember where) that these filters work by simply breaking the chemical bonds of the Chlorine/Chloramine which causes the remaining ammonia to be released. I don't know how much this releases. Do the chemical water conditioners work differently or isn't it anything to be concerned about?

It's been 30 years since a studied chemistry at school (I wasn't very good either ) but I wish I'd paid more attention!

The water here has chloramine in it. I use Seachem Prime to get rid of the chloramine. I also heat the water out of the tap to the approximate aquarium water. I then let it sit for 10-15 minutes. That's it.

I just add Prime to the tank as I begin adding tap water of approximately the right temperature to the tank. No storing, no letting it sit, no worries, no problems.