Bloating?

Housing
What size is your tank? 1 gallon (planning to buy a bigger one once I get paid)

What temperature is your tank? Not sure the water is usually lukewarm (planning to buy a stick on thermometer once I get paid :/ )

Does your tank have a filter? Yes

Does your tank have an air stone or other type of aeration? No

Is your tank heated? No, but it does have a light and I heard it does warm the water up a bit.

What tank mates does your betta fish live with? He's alone.

Food
What type of food do you feed your betta fish? I just started using Hikari Betta Bio Gold pellets. Before that I used flakes.

How often do you feed your betta fish? Twice a day. 3-4 pellets and the flakes 1-2 when I used to use them.

Maintenance
How often do you perform a water change? once a week.

What percentage of the water do you change when you perform a water change? I take out 75%

What type of additives do you add to the water when you perform a water change? Nutrafin Betta Plus (contains almond leaf extract, if that matters)

Water Parameters:
Have you tested your water? If so, what are the following parameters? N/A

Ammonia:
Nitrite:
Nitrate:
pH:
Hardness:
Alkalinity:

Symptoms and Treatment
How has your betta fish's appearance changed? He was bloated as if he had dropsy however within a couple of minutes after I noticed the bloating he'd become skinny again.

How has your betta fish's behavior changed? Nope, still curious and active as ever.

When did you start noticing the symptoms? The first bloating was a couple of days ago. He was extremely bloated last night however after 5-10 minutes he was skinny again.

Have you started treating your fish? If so, how? I've decided to fast him for a day or two because I'm starting to suspect that I've just been over feeding him.

Does your fish have any history of being ill? Just barely got him.

How old is your fish (approximately)? I have no clue, but he seems to be very young. Probably not even a year.


Also, I just bought him a red silk plant and I saw him resting on it. Is that normal? I'm very scared for him. I don't want him to die. I read up on the bloating and I'm starting to think it's just constipation and overfeeding.