I have fiddled again with the filter contents since last mentioning it here (squeezing and rinsing things in filter water in small bucket, to maintain the bacteria colony). Now I have it with the denser sponge and ceramic rings. I strung the rings in a few groups onto fishing line tied off, so I can lift them out in bunches instead of individual. Filter flow is going well with no overflow- more 48 hours now and nothing slowing it down. I guess I simply can't put poly in there, unless I want to deal with a bit of overflow all week. Disappointing because I did love the clear look with the fine particles all out of the water. I've seen another kind of filter media in the shop- a bonded filter pad able to cut to size, which might be slightly less dense than the poly and suit my purpose. But I don't want to try changing anything again now. Tank water tested fine yesterday morning- no ammonia, and nitrates 20-30 (recovery from the ammonia spike with dead snail).
However Snaky Fish is not looking good. I am not sure but I think the ammonia spike probably weakened him again. Next friday is the second scheduled round of levamisol to wipe out any remaining parasites, but I am not sure if he will make it. Two days now I have not seen him eat, he lies on one spot of the tank not moving. Bigger kuhlis run over him and he just lets himself get pushed aside. I fed garlic-soaked betta pellets two days ago- just for the kuhlis, in the trap. Snaky Fish didn't come for food. I dropped a soaked pellet right in front of him and he didn't move- neither to run away from my hand, nor to take the food (bad sign). When I fed minced pea yesterday, he did not stir to look for food (everyone else scurried like crazy). At the end of the day I put another half a pea in the food trap- the black kuhlis swarmed the entrance immediately. Albert showed up later, made it in before all the pea was gone. He is looking nice and robust now. The thinner black kuhli doesn't look skinny behind the head anymore, only way I can tell which one is his midline or spine still a bit visible thru the side. Snaky Fish did nothing.
This morning I could not see him anywhere, so with dread I tested the water to see if there was an ammonia spike- nope. I am waiting for the light to turn on to see if I can find him anywhere. Last night I kept checking for gill movement. I don't want to euthanize him....
The female cherry barb with bitten tail looks better. It seems to be growing back already but hard to see because the new fin is clear. She got the last bite of pea last night- when the black kuhlis were so stuffed they couldn't move and Albert had left the trap I lifted it out, one last bit of pea fell into a clump of subwassertang. The fishes could smell it- kuhlis who had been resting from gorging themselves came poking around and the barbs too, but they all look on the ground. Finally a female barb found the bite in the subwasser, and it was the one with the injured tail. I felt glad for her.