I'm thinking so too as far as the biozyme. My curiosity on that particular product came about because a friend of mine who has been keeping fish for 20+ years swears by it. I had a nitrite problem similar to what Fish Fanny is having on her tank (assuming you have seen her thread) in my Mbuna tank a while back, and because the ammonia in my water, the nitrites kept spiking when i would do a water change. When I spoke to her about it, she basically told me that I would have to let the nitrites take its course and that adding my ammonia water was just going to make it worse and stress the fish doing that many water changes. So she recommended it to me. I started using it one the tank, and within three days, the nitrites were done. I do not know if the product worked, or if the filter caught up. The tank has been stable since.