Does my betta have fin rot?

My betta recently has been depressed and pale compared to the usual, so I have added a new plant (as opposed to a plastic leaf) and heater which he seems to enjoy. While he is looking better (and his water is also looking better), I am wondering if anyone knows if this is fin rot, or if it is just a rip that he can heal on his own. I don't want to treat him for something he doesn't have but I do want to treat him if he needs it.

As an aside, I have been starving him a little for almost 2 days because he seemed to be constipated (also looks better than he did, but still has stringy poop stuck to his bum whenever I look at him) he has so far ignored peas when feeding them to help with digestion, but I think that is a work in progress.

The edges look a little black to me so I say fin rot. Treating it is rather straight forward, but can take a long time for it to clear up completely. Avoiding it is easier by doing weekly water changes. I'm glad to hear you bought him a heater, but does he also have a filter? Daphnia is a far better food for constipation than peas (for bettas anyways).

I don't have a filter, but I do water changes quite often. I first noticed his back fin had a chunk/scratch a while ago when we travelled, but I heard that they can heal that on their own best. (long story short about the travelling, I've had this betta for about 3 years and my first encounter with him was a seven hour drive in a cupholder in my car to get home. He has had car rides to visit family (3-4 hours each way) around 2-3 times a year, plus moving 3 times since I got him. I thought the scratch could have gotten worse simply by stress of the car rides, which should be getting better because we've been settled for a while now, but hasn't gotten any better.) I've read about the treatments, I just wasn't completely positive is all.

I read peas help with the digestion but they just sink to the bottom, so ill try out (is it a type of food or medicine??) the daphnia if it doesn't look better by tomorrow. I do want what is best for him, I didn't expect to be so attached to the little guy.

Other than this scratch that seems to have turned into fin rot (I assume by stress), and the recent constipation (I just moved in with someone who also feeds him so we will now have a schedule so he doesnt get over fed), he has been so (surprisingly) healthy! Over the three years his water has been super clean and he makes what I like to call love bubbles (baby nests ) .. however ever since moving to my new place (September) is when he started to go pale and sad and everything mentioned above. I think it was colder here, which is why I got the heater, and also a lot bigger, so we aren't always sitting in front of him. I've moved him to the most used room to keep him company (only downside is its a bit darker), and added the live plants last week. I just want to see his love bubbles again! I want him to be happy!

So treating him, I should be taking everything out of his tank (plants and rocks) in order to do this?

Thank you.

His name is Fraunhofer, by the way.

Just for reference, he looked like this 3 years ago in the pet store ( dark background with some sort of black light to enhance colour ) and what he looked like after I got home and set him up (again, around 3 years ago) (with the bamboo and brown background).

Daphnia is a food, it's actually a little water critter that all fish love. You should be able to find it frozen or freeze dried in a good pet store. How often does he get fed and how much each time? Also, what type of food does he get? I've hear loads of people have problems with their bettas getting bloated/constipated but I've never actually experienced it myself. I think it's caused by feeding them too much or irregularly, especially if it's the wrong kind of food.

Moving from one area to another can lead to problem mainly because the water parameters from the old supply can be different to the new. If the pH is vastly different from one area to the next, it will definitely cause the fish to get shocked because it can't adapt fast enough. This may be part of the cause and would certainly cause him to go pale and act lethargic. Your little tank could also very well be going through a Nitrogen Cycle, which no fish should ever have to go through. It's really tough on them and they often become ill. If you don't know the nitrogen cycle, you might want to look into it, it's very important in aquariums. This is often where people start asking what your water parameters are, which can be checked via test strips or by taking a water sample to your local pet store.

As for the fin rot, the best cure is keeping the water very clean and warm. I would be doing 50% water changes every day or at least every other day. There isn't much medication I would really be using, other than maybe quick cure as a bath every other day. It's mainly meant to cure the parasite Ick but it works on fungus too.

I really recommend buying a small filter. There's several different types for micro tanks, most use an air pump but they seem to work well enough. Filter are vital to all aquariums, that's where most of the good bacteria that breaks down the fish waste lives (huge part of the Nitrogen cycle). If he is in the same tank as the one in the picture with the bamboo, I really suggest a larger tank. I say 5 gallons is perfect for bettas, some say 10gal. I have all my bettas in ten gallon tanks. My sister keeps her male in a 2ish gallon tank and he is doing great too.

Btw the live plant you have is called Elodea (i think) and needs rather high lighting. I ended up killing mine because my tank is low light

Hi, my tank is about 1 gallon, made by marina betta (which came with the fish food and water conditioner that I use) With it being small, it is easy to clean (thankfully) so I do water changes multiple times in the week. I think I will get a filter for him and bring a water sample next time I am in the pet store (probably tomorrow, I also have a rat and bunny so I frequently stop by). The plant is anacharis, I will read more about it now.
I feed him a small amount of betta flakes twice a day. the past little while, I think my boyfriend was also feeding him thinking I hadn't, which is how he got constipated.