The number one error that fishkeepers make when they are first starting out is not removing chlorine from their water. All tap water contains chlorine. Your city water supply adds it in to prevent bacteria and algae in your drinking water. In aquariums and tanks, that water will quickly burn a fish's gills and will kill in minutes.
Seachem Safe is a product we use everyday in our commercial fish farm. We love this product.
It works in both fresh and saltwater. It immediately removes chlorines, chloramines, and any ammonia. If added to tap water, it makes that water usable immediately without the need for having to store it and wait for the chlorine to decay.
Safe also detoxifies both nitrate and nitrite, so if you are cycling a tank, and run into an unsafe condition it will immediately correct the issue allowing you to save your livestock.
It will not impact pH.
We use it every time we add or replace any water in our tanks.