Does my betta have fin rot or is he nipping himself

I saw my betta curling around and trying to get to his fins yesterday, and he bit his own tail. The top part of his tail has been deteriorating for the past week and today I saw a round hole missing from one of his fins. I don’t know if this is fin rot or a combination.

There haven’t been any large changes to the tank. He acts normally, swims energetically and has a large appetite. I feed every other day. He lives with 4 albino corydoras and 7 kuhlI loaches in a 20 gallon. What should I do?

 

It looks like a touch of finrot, if a betta starts nipping its tail there must be a cause. I would test your water to see if poor water quality is to blame.
I wouldn't go to medication straight away, as it's only mild I would try keeping the water very clean with daily water changes ( 25 percent ) and maybe a little salt for a few days.

 

Fin nipping can be a sign of stress or aggression. This does look like it could be a combination of both nipping and mild fin rot but likely began with the nipping by the looks of the tail. Having torn and damaged fins opens the possibility for further infection. Pinholes in the fins are easily regrown with fresh water, some stress coat might not be a bad idea either to replenish slime coat.

It could also be your lighting as my youngest of my 3 bettas has a fairly bright light next to a black bookshelf and this sometimes causes him to see his reflection against that part of the tank. Excessive flaring can also cause tears in the fins and in turn more stress so turning down the intensity of the light might help in that situation.

Lastly it could just be that the fish is feeling weighed down due to the size of it's fins which I believe is less common to induce fin nipping but nonetheless is a possibility. Keeping them occupied with a "new" environment can be an easy distraction from the temptation to nip. Perhaps adding some resting spots but the surface might help alleviate the work of dragging it's fins around.

Edit: also be sure to check for the obvious, sharp or jagged decor!

 

Got it. I’ve removed any reflective surfaces from the tank, the last photo was me putting a black notebook up to get him to flare so I could take a photo of his full fins. I’m doing a water change now and I’ll order a betta hammock? Do you think I should buy a hospital tank or can he stay in there for now? I don’t think I can add salt because the kuhlI loaches don’t have scales. Thanks everyone for your help.

 

Although a hospital tank is not essential for treating fin rot without meds. it's a good idea to have one anyway in case you have to medicate a fish in the future. You don't need anything fancy. Mine is a 15 L plastic fish tank with a small sponge air driven filter and a cheap Chinese 25W heater.
I have no substrate and some cheap plastic plants ( they look rubbish but provide cover ) as a cave I just have a plastic pipe fittings I found in my barn.
Avoid live plants or anything you can't clean thourghly. I cycled mine years ago and after use I clean everything but the filter, then to keep the filter alive I add one drop of pure ammonia each day when not in use.
A hospital tank can also double as a quarantine tank when you buy new fish. When using mine as a quarantine tank I add a second air driven filter loaded with carbon. Don't use carbon when medicating fish because it will remove the meds..

 

The hammock or some floating plants would make a nice resting spot. He will probably be ok in the home tank, bettas are pretty hardy as long as you keep the tank and water clean. However a hospital tank is never a bad idea to have on hand.

Flaring in excess can be bad and cause fin damage but for brief occasional periods can actually be like going to the gym, building stronger rays/fins and the bettas confidence after having successfully defending it's territory. It can also be an outlet for possible pent up aggression the fish might have. Key for now is to keep the water clean and keep an eye on his fins and behavior.

 

Great, thank you so much for all the advice! I will keep doing daily water changes and keep an eye on him.

 

This looks like fin rot and nipping, maybe nipping because of the rot or the rot happening because of the nipping or some combination.

Had that on two of my current bettas when I first got them. If the kuhlis can’t handle aquarium salt and you don’t notice any improvement in a couple days, I highly recommend a small hospital tank for 10 days or so. Dose with appropriate salt and tannins with plenty of silk plants to offer resting and hiding places, water change every other day of 50%.

You could also add in something like stressguard or Indian almond leaves or rooibos Tea for the antiseptic qualities/tannins.
Big/Daily water changes are sometimes needed in very bad water conditions but in my experience it’s incredibly stressful on my fish, especially Bettas.