Redundancy just saved my fish! I did a 50% water change before I left on a 3 day business trip from which I returned last night. This morning as I was watching my fish at breakfast, a terrible thought hit me. I couldn’t remember plugging the HW-3000 canister filter, which is the primary filter for my tank, back in. I checked, and sure enough, it had been unplugged the whole time. Fortunately when I set up my tank, I had added a couple of box filters filled with Seachems de nitrate and a couple of small sponge filters with additional media compartments that I had filled with de nitrate, all of them run by a single air pump. My fish were not showing any visible signs of distress. I immediately tested my water and although not great, I was relieved to see that the ammonia was only .5 ppm. If it were not for the additional air pump driven filters, this would have been a much bigger disaster. (Tank: 125 gal. Fish load: 6 approximately 4-6 in fish)
