ATF Split Fins with Light Off

[Lobonator]

Just wondering if anyone else has had a similar situation.

I have my ~8" TATF in a 125 gallon grow out with lots of flow. Water parameters are good, and filtration taken care of by two fx5s. Every time I turn the light off overnight, when I go to feed him in the morning he has multiple splits in both his caudal and dorsal fins. When I've left the light on for a couple of days the fins seem to heal up fine, and don't seem to split at all. The only other fish in with him are a 3 red hooks, that don't go anywhere near him, so I know they arent causing the splits.

If anyone knows what could be causing this, I'd love to know because its obviously not great for me to leave the lights on 24/7.

Thanks in advance!

Aidan

 

[Justin David]

Ive had fish that feared another during daytime but attacked the same one when the lights went out. Its like they swap roles..try taking a look at night. its worth a shot

 

[Lobonator]

Alright, I'll give that a try tonight and see if anything is happening. Do you think a moon light would help if something is going on at night?

 

[Justin David]

Not sure about the moonliight, did you see anything?

 

[Lobonator]

I checked multiple times last night, and there seems to be nothing going on. But in the morning there are splits in the fins again. Just to clarify, they aren't torn or bitten. The "splits" (dont know hat else to call them) are straight lines between the rays in the fins. Very strange!