Algea and huge danio problem

[Dms02a]

Hi everyone!
I posted back in December about my danio who is super fat. His name is hulk because he is huge never stops growing. I’m concerned. I asked if it was pregnant or sick maybe. Everyone seems to think it will just eat until it dies. It has gotten even bigger despite diet. It fights the other two in the tank for food. I have tried feeding them in separate places but this is where we are. What should I do for it?
Also I have a 10 gallon tank, with the LED lights that came with it. I only leave it on during the day. However I have an algae problem. It grows so much I have to clean very frequently. When I put a filter in it turns green almost immediately. Tips!? Please help! Trying to be a better fish mom.

This is what it looked like in my first post: December 2020

This is what it looks like now. Quite startling when you see them side by side. His attitude has not changed at all during the past couple months.
I just cleaned the tank due to do the algae and now he is acting a bit weird.

 

[Colin_T]

could be a female with eggs.
could be full of intestinal worms.
could have a growth/ tumour.
could be a combination of these.

what does its poop look like?
pictures of the other fish to compare it to?
when you take pictures, try to use normal light so the fish looks normal.