T. Payne

Appears to be a scud. Harmless scavenger and good fish food.

Stocking level of the fish would be fine.

Definitely ramshorn.

I have it in several of my outdoor ponds, it grows as fast as duckweed and I hate duckweed, so I won't introduce it into the fishroom.

Appears to be its operculum.

While I have never witnessed corydoras eating an entire snail including the shell, I commonly crush snails on the aquarium glass and my breeding groups of corydoras rush to them and eat them. I wouldn't imagine it being a problem for them consuming the shell as well.

Thats the one reason I do not care for hornwort, the plant dropping needles leaves a huge mess that must be removed manually.

The only floating plant my goldfish do not care to ear is dwarf water lettuce. As far the pleco goes, is it a male or female and what size aquarium is it in?

You should not have any issues keeping them with smaller species of tetras and corydoras.

Males will chase each other and display, I wouldn't consider them aggressive though.

Mollies 100%

Thats definitely a large older fish then. I've bred several species of psuedomugil, and while technically this isn't one of those species, I have never heard of one living anywhere near 5 years of age, far from a fast growing species as well.

Short lived fish, appears to be an older mature male. How large is the fish?

I would say this is a case of poor genetics on top of old age. Alot of rainbows get humpback with age, but the crooked spine is genetics.

Never had a problem with ich x causing water issues. I used it for years and if needed is a go to in my fishroom.