Ghost Shrimp eating Betta Fin?

I've got a new-ish community tank. My water parameters are cycled. Ammonia 0 Nitrite 0 Nitrate at 5ppm.
A 15 gallon stocked with 5 False Julii, 3 Kuhli Loaches, 5 Ghost shrimp of varying sizes.
It's planted and there isn't anything to snag on.

My question is could the ghost shrimp be eating my Betta's tail at night when he's sleeping?
It doesn't seem to happen in the day time. I firsts noticed his fins were a little torn yesterday and kept a close eye on him. Today the tatters are gone like they were eaten. He swims normally and showing no signs of distress. I have a ghost shrimp that is almost fully grown. I made sure that these were indeed ghost shrimp and not whisker shrimp unless I'm missing something. All the shrimp have the red banding around their antenna and claws. Claws are short, I've seen the Whisker shrimp and theirs are much longer and no red banding.
Could it be the shrimp are chowing down on him because initially I thought it was him from the move and tankmates but as I said before he is not doing it in the day time. I work from home and sit right next to the tank.

Should I move some of the bigger shrimp out? He's lived with these guys since I got them. Strange for them to start munching on it unless I am not feeding them but I feed flake and algae wafers everyday. Flake x2 a day and a wafer once a day(All the bottom feeders are juveniles) I can't imagine the timid catfish and loaches to eat the fin plus the location is suspicious as it's always the same spot at the top of the rear fin, the perfect distance for him to turn and bite(which I've nevers seen done). Or could it be that he is chewing it off himself due to a slight current in the water?

 

Not really familiar with ghost shrimp, but I imagine the only circumstance when any shrimp would eat fins of alive fish is if that fish has fin rot. Then, I could imagine shrimp munching on dead tissue. So maybe your betta has fin rot, which is why the tail looked shredded yesterday? In that case the betta needs to be treated.

 

I suspected that too but he does not have it all over and it's happening really fast with no white-ish outline to it. The finnage looks like it's been clear cut off. In the picture you see where there are parts missing. There used to be some fin there and the softer parts in between were missing. Those parts are now just gone and looks very clean. I'm going to move some of the bigger Ghost Shrimp out of the tank and put them into the community tank. I've also seen some of the bigger ones hold up their claws at the fish and wait like they were hunting? Odd since I thought ghost shrimp were pretty passive. The smaller ones seem okay it's just the bigger ones. Maybe a overcrowding situation for the shrimp.

I've moved the bigger ones. Pretty bold for ghost shrimp. Let's see what happens.

 

Is it possible that he is nipping his own fins? It does happen a lot...

 

It really does seem like it, but I can't be sure. I never see him doing it in the day time and it's such a big change overnight. Always in the same area along his headline as if he curled and bite some off. Stress? There isn't any current in the water anymore. Any suggestions on what to do or is this just something they do, I've never had a Betta do that granted I've only had 4.

 

It's hard to figure out what the trigger is....I had two that were fin nippers. I kept the water super clean. Made sure the lights were dim, and that they got a good 14 hours of lights out. I changed up a few things in the tank - what I could move around. Started using more Indian almond leaves so I had a good amount of tannins - made the water darker brown, rather than a tiny amount that just barely tinted the water.

I even taped some black construction paper on the back of one of the tanks so my betta couldn't see himself in the glass, and that helped for a good long while.

They both eventually stopped. It was a period of time when they were maturing, too, so I really think that had a lot to do with it, along with seeing themselves in the tank glass.

 

Ah that makes perfect sense. I've been doing some research myself and it seems to be a mystery. I was worried I was triggering something but He wasn't fully mature when I got him and he is finally starting to turn black in the head region and really change colors. When I got him he was blue and red. No green. Now he is showing green and changing colors. Also his body is more robust than a month ago. I guess it's like fish puberty Hahaha! His behavior does seem testy right now and everyone in the tank is taking it in stride but I have isolated him in another 6.5G and he seems okay in there but he does seem to butt heads into the glass when he sees himself now. Not a behavior he used to show. Thanks so much for the information. It was massively helpful to know someone else has gone through something like this. The torn fins worry me but he's super healthy. I've moved the shrimp back since they were the scapegoat for this .

 

My current guy does the headbutting thing now, too!! So aggravating at times! It's such a doofus move, lol!