Water replacement, tap water and Aquasafe question?

Specifically Yes, I have used Tetra Aquasafe before with tap water treated with Chloramine and it works perfectly fine. You would treat the tap water prior to putting it into the tank. I treat the water then let it sit for a few hours to adjust to room temp and completely work out all the harmful metals and chemicals before adding it to the display tank. As far as how much aquasafe just follow the specific directions on the bottle. I used it previously for a number of years and never once had any issues. Most of tetras products are trash, however as far as the aquasafe is concerned I would recommend it as it does exactly what it states. Hope I helped a little, and truly of best of luck with your fish.