Help me please!
My crowntail betta fish, Fred, recently started to not act like himself, and it has gotten worse as the days progress.
On Monday, Fred had parts of his tail torn off. The parts didn't look like tail rot, because there is no brown on the base, and I has not progressively gotten worse since then, his tail has remained the same since then. I thought it was a filter issue, so I wrapped gauze around the part of the filter where it sucks, and secured it with a rubber ban, so water can get in and out, but his tail can't.
On Tuesday, he began to hide, but in places of plain sight, towards the back. Fred never hides, ever, so this made me suspicious. He still ate and swam normally.
On Wednesday, he was still hiding and eating. I did a 50% water change, I changed the filter cartridge, and tested the water. Ammonia was at 0, as well as the chlorine, nitrate, etc. All normal levels.
On Thursday, began hiding in spaces that are hard to see. He stayed in one area for up to 4 hours at a time. Still, he ate fine, and there are no dots, marks, or any sign of disease on him.
Today, Friday, he has been hiding in the same area that is very hard to see for 5 hours, and hasn't come out. Still, there are no marks, and he looks fine. The ghost shrimp in the tanks, that has been in there for 4 months now, is still fine as well, and is acting normally.
Could anyone please help me! Nothing on the internet is helping me, and I am becoming desperate!