Oh, I forgot to add, I found them at Pet Smart :shock: They are in a screw lidded container with the other treatments. It was a last ditch attempt to save the tank that worked really well. Once they are dry you can store it until next needed. Using this method, no water changes were needed, allowing ...

I found some nitrazorb granules in a cloth bag that I fitted into my fulval 3 instead of the carbon filter. It absorbs ammonia, nitrates and nitrites really quickly, and is reusable. When the levels no longer decrease, you place it in salty water and then dry, ready to use again (reverse osmosis ...