Investigating what at first appeared to be a clump of fishfood stuck under the little hobbit house, I discovered a fish carcass that was fairly well along in the decomposition process. ::shudder::. Tom, normally our fishtender, is gone on a TDY, but it's only been since Monday; somehow I don't think it decayed THAT fast. I haven't kept track of our tank's demographics in a long time. I know we have a few neon tetras, a few orangish fish that I think are a different variety of tetra and KNOW are not goldfish, and a catfish. Rockbiter, a different variety of cleaner fish, was found dead on the bottom of the tank a few months back, and we've lost and added a fish or two of the other varieties at odd intervals.
If we'd kept a running tally, maybe we'd have noticed the dead one before it decayed so much. >_<
Current population of Picon:
4 orangish fish.
3 neon tetra.
1 catfish. (Call sign "Jabba")
I removed the carcass with the net and proceeded to clean the tank thoroughly. Unplugged the filters, heater, and light. Took out all the plastic plants, the hobbit house, and Jabba's beloved mini Japanese garden (this visibly annoyed him); scrubbed them all thoroughly by hand in warm water with no soap, and laid them out to dry. Rinsed out the filter cartridges and housings, and the heater. Removed roughly half the dirty water. The only time we've "cleaned" the gravel since we started keeping fish last fall was when Tom decided that it was easier to switch from 10 gallons to 20 gallons like we wanted to than to actually clean the 10 gal. tank, and simply start over with entirely new gravel. So I scooped most of that out and started rinsing it in small batches, then setting it aside. By the time I'd removed half the gravel, the remaining water was looking grim, so I stopped scrubbing the gravel and removed it all in a hurry. Then I added fresh water with drops of Prime by the gallon until it was deep enough for the filter intake tubes. Got one filter working again, and waited to see how the water looked. The larger filter started making noises as soon as the water level reached the bottom of the intake tube, and began chugging vigorously as soon as I poured water through the cartridge.
Around 10:30 the water was looking vastly improved, but not quite enough for me to feel good about leaving it like that overnight, so I removed and replaced several more gallons. Right now it's cloudy and very faintly tinged with green, but the fish are readily visible and most of the large gunk has either settled to the bottom or been filtered out. I put the hobbit house and Japanese garden back in so the fish would have places to hide until I was ready to fully reassemble the tank. If the water's looking acceptable in the morning I'll finish rinsing the gravel then, and put everything back in.
At present we only have one filter working. When we switched from the smaller tank, Tom kept the old filter and installed it in the new tank next to the new filter he bought for it, on the grounds that two filters had to be even better. We've replaced the cartridges regularly; and I rinsed the cartridges before turning the filters back on. But for some reason the smaller filter will not start up again. It has an upsidedown U at the top of the intake tube, whereas the larger one has a straight intake tube. I have tried removing the tube, turning it upside down in the tank to fill the bend, holding my hand over the shorter end while raising it, and popping it back into place, so that the siphon effect would start up again. Didn't work. I've tried unplugging it, inverting the whole thing into the tank, and holding one hand over the intake pipe before and during raising it, and turning it back on. Got a brief chug and then nothing.
One filter ought to do til morning, now that the water's cleaner, and I plan to get a new catridge for the working one tomorrow. Any suggestions on how to get the other one back in action? Any suggestions on what other steps I should take? Tom won't be home for a bit, and remains mostly incommunicado, so I can't ask him.