My mother has a fairly large pond and loves it to death - it's become her new hobby. The problem is that she tends to forget that the garden hose is on when refilling it and there will be a chlorine off balance that kills the fish. I was wanted to get some kind of attachment that filters out chlorine to prevent this from happening and making the pond safe for fish no matter what. There are just so many websites to buy them from and there's huge variances in prices so I wanted to jump on here and see if anyone had any suggestion on the kind of brand to get or the website to buy it from. Much appreciated!