You wouldn't necessarily smell ammonia--but there are test kits that will check for it, and they're pretty cheap--look in the aquarium section at WalMart or any pet store. Since you're been fighting this long and it still hasn't cleared, I would check to make sure that's what you're actually fighting. I guess I have been assuming all along that we knew for sure that there was ammonia in the water. It's the only reasonable explanation that I can come up with right now, but maybe we need to verify it.....

Janet