We recently purchased a male betta and brought him home. He wasn't incredibly active after acclimating and being added to the several-month-old tank, replacing a different betta that was moved to a different tank. Since then, however, we've noticed disturbing and worrying behavior (or lack of behavior - he is like a zombie).
He was in a 5.5g filtered tank, heated to between 80 and 82 constantly, with a cory and a small mystery snail. I am not sure he ate anything, but if so, it was a few frozen blood worms one time (He would have had to have eaten them when my back was turned) and maybe a drifting pellet or two. We've tried to feed him every day for the past five days, but have not seen him eat.
After day two, I became concerned by the lack of movement and slight loss of color and quarantined him and the other two betta in the house, for fear of cross-contamination through nets, droppers, etc. He is now back in the cup receiving water changes every 12 to 18 hours with conditioned water (API StressCoat) and the stated dose of API BettaFix (Melaluca, I believe?) in his water each time. His cup remains floating in a heated tank at the above temperature. We have been dosing BettaFix for three days, now.
The water seems to test safe, with a pH of 7 - 7.5. He barely moves, doesn't eat, and floats to the side. He seems a little bloated to me, but it's hard to remember day one versus day five, and we haven't seen him eat anything. Haven't seen any waste in the cup, either. Of note, there was a small tadpole-shaped balloon-looking attachment that was noticed on day three, but it fell off during a water change last night. This morning, there is a fine tendril near the same place the that attachment was. Is it possible he has a parasite of some kind? His colors seem to have dulled and he drifts onto his side at times, but mostly stays at the top, unmoving until the cup is disturbed, and then only barely.
Does anyone have any other suggestions? I hate to see the little fellow suffer, and don't know what may help him, but he can't go but so long without food, right?