When changing water...

[Aven]

Do you put in the water cleaner before its in the tank or after? Do you even have to add the the water purifier? (my water is unchlorinated, it comes from a well) Thank you!

[Oldfishlady]

If you are on well water you shouldn't need dechlorinator.
I have/use well water and never use it unless I clean a tank with bleach and then I use it with my first fill before fish are added. I always keep it on hand..just in case....

[BerkB33]

The only thing I would add is that some wells have a high metal content. It might be prudent to test it for metals, hardness, and pH. That way you know what you're dealing with and often times it will help when problems arise.