"closed cover disaster" Please explain.?
I'll try to make this brief. Every time I relive this I want to punch somebody. 10 years ago when my family and I moved to N.C. we finally had enough money to set up an aquarium, something I didn't want to do in Florida because I knew I wanted out of there. OK, I digress...
I bought my current 180 gallon aquarium which came with a custom stand, and glass covers which, when closed, completely seal the tank. I never knew about oxygen and carbon dioxide problems because my previous tanks used HOTB filtration, there was always an opening in the back. After this tank crashed the first time (combination of the covers being closed and a heater exploding and shorting out, but I still didn't know about the cover thing) I left the tank fallow for 7 years.
When my wife passed away 8 months ago she left my son and me enough money to get the tank going again. With my arthritis and other ailments I just couldn't physically get under the tank and plumb in the new filtration so I let my local LFS do it (for a hefty price, no less). When they were done adding substrate, replacing the live rock and filling it with water, they placed the glass covers back on the tank AND CLOSED THEM!!!! They didn't warn me about the dangers of leaving them closed. In the meantime I had cycled the tank and stocked it with all the fish I wanted in the tank. Things were going great until....the fish started dying, 1 and 2 at a time. All of them were completely healthy and eating the night before, all died by morning. At the end I had nothing left but 2 of my 3 Yellow Tangs, my Bitch on Wheels Queen Angel, and the usual indestructible assortment of damsels, crabs and shrimp.
When I told the guys at the LFS what was happening they said there must be a disease that strikes at night or some nonsense. It wasn't until I'd lost all those fish that one of them asked "Do you have covers on your tank?" "Yes." "Do you keep them opened?" "No, I thought you were supposed to keep them closed to keep dust out and fish from jumping". "No, you have to keep them open. Otherwise you're keeping oxygen..." blah blah blah you know the rest. So they basically waited until I'd lost over $1,000.00 worth of fish before telling me not to close the covers, something THEY did when they finished up the install.
Grrrrrr.......
