Fin Rot or Fin Loss?

Dolphin, my (I think half moon) betta, is experiencing fin loss.

A few months ago, after a stressful move, he had fin rot which I treated with daily water changes and aquarium salt. He never fully grew the fins back to their previous state. At the time he was also in a 3.5 gallon tank (with heater & filter). tThat’s what I could afford at the time as I saved him from my roommate that kept him in a small bowl.

Now he is happily swimming in a 15 gallon planted tank, with built in filter & adjusted water flow, air pump & heater.

The water parameters are fine, and I check them on a regular basis. I do weekly water changes and I always keep an almond leaf in the tank. His only tank mates are MTS and pond snails. Hydra is also present at the tank (I tried to rid of it using aquarium salt, which worked only temporarily, but that’s a problem for another post. since then I water changed the salt out).

I would notice mild tears in his tail, but they heal up quickly. This time it’s much more severe. I’m not sure what’s it’s from, but it looks different than his last battle fin rot. Looking closely, I already see white-ish edges, that with him usually indicate recovery.

He eats fine and seems health otherwise. I don’t know if I should interfere and needlessly stress him out with water changes or try to let him heal up by himself.

Also, the clear edges are from his previous recovery, and the fin loss appeared over night.

Salt won't get rid of hydra. Presence of hydra, clam shrimp, cyclops, planarians, detritus worms and seed shrimp is always an indicator that your substrate needs thorough cleaning.
We still need the exact numbers of your parameters.
He is tail biting.

It looks like someone is taking bites out of his tail.

What other fish are in the tank?

Colin_T said:

What other fish are in the tank?

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Probably none. I agree, the betta is biting his own tail off.

Colin_T said:

It looks like someone is taking bites out of his tail.

What other fish are in the tank?

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none! that's why I'm so confused. I scaped the tank especially for him, made sure there are no sharp edges anywhere, and the places that might hurt him are covered with a disected moss ball...

Keels said:

none! that's why I'm so confused. I scaped the tank especially for him, made sure there are no sharp edges anywhere, and the places that might hurt him are covered with a disected moss ball...

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He is biting his own tank. It means he's bored.

Can it be that he is too bored? needs more stimulus? should I consider adding a bottom dweller? idk what else I can do for him

First, you need to see how he'll do fine with couple of tank mates (like nerite snail, maybe one or two guppies). First try mve things around when doing your weekly water changes to keep thing interesting to investigate.

Tail biting can be caused by stress or boredom.

You can try putting a mirror next to the tank for 5-15 minutes. Then move it away. The fish will flare up and show off to its reflection and after you remove the mirror, it will think he chased the intruder away. Do this once or twice a week.

Try feeding him different types of food. Live mozzie larvae, daphnia and brineshrimp can give him something to do.

And also moving things around

Salty&Onion said:

Salt won't get rid of hydra. Presence of hydra, clam shrimp, cyclops, planarians, detritus worms and seed shrimp is always an indicator that your substrate needs thorough cleaning.
We still need the exact numbers of your parameters.
He is tail biting.

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the hydra came with the plants, and from my research it doesn't come from dirty substrate, but it can contribute.
Salt did kill the existing hydra, but they repopulated again a week after I took out salt. I got the advice from @Colin_T .
I ended up ordered dewormer which should arrive soon.
the tank is only 2.5 months old. well cycled. I make sure to get dirt from substrate when doing weekly water changes.
0 ammonia/nitrite, 10ppm nitrate.
I can't move things as it's heavily planted (attached picture.)
I let him flare a bit every over day.
he seems fine with the existing snails in the tank, never flaring at them or attacking their "antennae"

I see you're doing really great. I suppose he should be fine with a female guppy or two. Hydra does hitchike with plants, I saw one in my bettas tank which came from dirty substrate. Did nothing about it except cleaning my gravel and doing a little water change. Try that.
For his tail biting, see if you could add two female guppies (best if endler females as they're plain) and rearrange his decor.
Ask me if you want to know how to add other fish to betta tank

Salty&Onion said:

I see you're doing really great. I suppose he should be fine with a female guppy or two. Hydra does hitchike with plants, I saw one in my bettas tank which came from dirty substrate. Did nothing about it except cleaning my gravel and doing a little water change. Try that.
For his tail biting, see if you could add two female guppies (best if endler females as they're plain) and rearrange his decor.
Ask me if you want to know how to add other fish to betta tank

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I do want to add more fish, but I'm really worried about it.... and I would love some advice on that!

that's what I know / my concerns:
1. he is my introduction to the hobby, and never had any other fish to care for but I would love to expand!
2. can't afford anymore fish tanks rn... I do have his old 3 gallon as emergency hospital tank.
3. from my research, it was recommended to add other fish first, so he won't get as territorial... and now that he has been there for a while, idk how he'll react. he does seem pretty chill though...
4. If I do add more fish, shouldn't it be more than 2? in case he does chase them around, he won't be able to pick on one

please let me know your thoughts and advice about how I should go about it

Don't add guppies to a tank containing a male Betta splendens. They require different water chemistry (Bettas have soft acid water, guppies have hard alkaline water), and the Betta could attack and kill the guppies.

Dirty tanks don't make any difference to hydra. They come in on plants and ornaments and divide and spread through the tank. You can have a really clean tank or a filthy tank and they can both have hydra.