Abdominal swelling

[avz10]

I have previously discussed the problems that I have with abdominal swelling and in the last year I have had 3 deaths because of it.
The one with current swelling is the white one(1st two pictures) (I'm a newbie!!)(What are the black spots?).
I also need to know about pop eyes-Should I do anything about it(3rd picture)
Could someone help me to name my fish in the fourth picture?
The last picture shows one of the fish that have died.
Any advice will be helpful!