I was reading about Total Dissolved Solids and was wondering,wouldn't dechlorinators contribute to the T.D.S.? I don't use ANY additives for this reason...........Carbon,softening pillows,ceramic rings and ammonia rocks have had my water diatomaciously-clear for ever,so i was wondering if it was even necisary to treat tap-water if it's part of a 15-20% water change on a large tank.Won't the water in the tank dillute the new water enough?? I'm leery about putting ANYTHING into my tanks......concerned with the buildup of T.D.S.