What's wrong with my betta, hanging in corner?

I just got my betta and he was already in a bad shape when I got him. I was hoping that I'll be able to help and treat him. I am just unsure on what's wrong with him. He's not swimming at all. Just in the corner of the tank. I am assuming it can be swim bladder but I'm unsure and if it is, is it possible to treat it? Please help.

5 gallon tank with live plants and hanging filter.
All water parameters are normal.

 

Usually i start with fasting if swim bladder, as it is often a by-product of bloat. However, i am currently leaning towards new betta, new tank, so getting used to new environment and possibly some stress about it. I would try keeping the tank lights off as much as possible for the next couple days and help him ease in. Or maybe add some hiding spots. Currently dealing with this myself with a new king betta.

 

I am genuinely hoping that's the case for him. I'll keep an eye out for him. His breathing is also minimal. Barely seeing his gills move unless you take a closer look. I was planning on fasting him but do you think giving him food might be a good idea?

 

How long do yoi have him? If you provide him some hiding places with lots of plants or a Betta log, he may appreciate it. Also a Betta hammock is normally accepted to be able to rest under the water surface. Lights out as well to not stress him out more, an Indian Almond Leaf or some Stress Guard may help as well.
Then there are all the questions.
How old is the tank, is it cycled, does it have a filter and heater, what is the temp, what are the tested parameter values, how often do you change water.
I may be wrong, but in my opinion he looks a bit on the skinny side, so I am not sure why there would be a need for fasting. In the contrary, I would try to get him some frozen food (bloodworms, brine shrimp, daphnia) may be in garlic juiceto entice him to eat a bit.

 

How long do yoi have him? If you provide him some hiding places with lots of plants or a Betta log, he may appreciate it. Also a Betta hammock is normally accepted to be able to rest under the water surface. Lights out as well to not stress him out more, an Indian Almond Leaf or some Stress Guard may help as well.
Then there are all the questions.
How old is the tank, is it cycled, does it have a filter and heater, what is the temp, what are the tested parameter values, how often do you change water.
I may be wrong, but in my opinion he looks a bit on the skinny side, so I am not sure why there would be a need for fasting. In the contrary, I would try to get him some frozen food (bloodworms, brine shrimp, daphnia) may be in garlic juiceto entice him to eat a bit.

My tank's been well cycled for over 2 months now with plants and a cave. I did a 50 percent water change a couple of days ago. But usually I do a 25 percent water change every 2 weeks. I got him a few hours ago and bettas here in my place are on the neglected side and he was one of those. They were reluctant to sell him to me cus he's in a bad shape but I wanted to at least give him a good life and let him be comfortable. I checked the water parameters a while ago using the API masterkit and everything's normal. It has a hanging filter with some bit or carbon in it. For heater there's none cause it's hot in where I am. I also made him makeshift betta log but he's not really interested.

Temp 26°C around 97 in farenheit I think
pH 7.6
Ammonia 0 ppm
Nitrites 0 ppm
Nitrates 0.25 ppm


Update on him. He suddenly fell?.. on the substrate and this is how he looks right now.




Another update:
He is back on the surface of the tank. I removed the carbon off my filter and added some API General Cure. Just in case. If you'll look at his body from below, he looks really thin. I tried offering some pellets and flakes but he didn't touch them. I'll try to loom for bloodworms, daphnia, etc tomorrow.

 

Yes, fasting him won't get you anywhere.
If you can get him some tannins and a spot a bit higher in the tank so he would not have to work as hard to get to
the surface, that would help. See if you can get some garlic juice, it is supposed to be appetizing. Keep us posted how it works with the frozen food.

 

He's just floating around now. And just letting the tiniest current of the filter move him around. (It's on the lowest setting) he's still breathing but irdk what to make out of it. I'll go buy him some food now.
I moved him to an isolation container and he's just.. vertical.



I bought him some tubifex worms because that's all the petshop has but he has shown no interest. He's still vertical.
Hi. He didn't make it. Thank you for all of your help.