Has anyone prefiltered their treated tap water with zeolite "before" adding it to the tank? Just a thought. A small, internal filter(filled with zeolite) dropped into the bucket of treated water would work great. I've often wondered about the build-up of nitrates in tanks when chloramine treated tapwater was used when making water changes. In a planted tank, where nitrates are desirable, this shouldn't be a big deal, but in fish-only tanks how would you control the nitrates other than using RO water? I would imagine this to be a bad thing in saltwater and reef tanks, especially. I guess it all would depend on the actual amount of nitrate being produced from the nitrification of the ammonium after the water is treated with the water conditioner in relation to the amount of nitrates removed from the water change. Would this amount of nitrite(from chloramine) be considerably less than that which is being removed from water changes? Probably so, since the fish and organics within the tank are also adding to the total nitrate concentrations...doing the water changes is, more than likely, reducing the over-all nitrate concentration, even though ammonia/nitrate is "added back" during the water change. Seems that prefiltering the water, with zeolite beforehand, would eliminate this issue, without having to use it in the tank's filtration system.
