History and parameters: 29gal Temperature: 75 deg Ammonia: .25ppm Nitrite: 5+ ppm Nitrate: Haven't checked in a while but at last test it was relatively low ~ 20ppm pH: 8.2 About 6 weeks ago after an exhaustive search for a suitable bottle of ammonia and not finding anything I started my fishless cycle with fish food. Two weeks ago I finally got a nitrite reading and have been off the charts since while ammonia has been dropping. My concern now is that without a way to actively control the ammonia level it will get too low and the bb colony will suffer. So should I do anything differently? Ultimately I am planning on keeping tetras and cory cats. Now that I have some bb could I get a few fish and gradually get more while keeping an eye on my parameters? Or should I stay the course and wait for ammonia and nitrite levels to drop to zero?