hi and welcome,
we pass through Chappell Hill on the way to the Blue Bell factory :)
sounds like you're doing it correctly.
if you don't start seeing nitrite or nitrate next week, you can skip a water change and dose Prime. Prime will detox ammonia for up to 48hrs. so it would be water change...
please fill out the emergency template so we can get more info. we definitely need water parameters, tank size, how long you had him, how long has he been floating, what food you feed him, etc.
he also looks like he has either fin rot or the fins got shredded by the filter.
has he been getting...
if you don't have Prime, add some aquarium salt. that nitrite is causing methemoglobemia which blocks the transport of oxygen inside the fish's body, they're not getting enough oxygen.
you'll also need to do more frequent water changes (like every other day) until the nitrite goes down to 0.
is the belly evenly bloated or is it more to one side?
was she floating to one side? or was the tail floating up?
try the erythomycin, seems to be some internal infection causing the bloating and blood spots.
the air pump pushes air down into the sponge. as the air bubbles leave the sponge and rises up towards the surface, they create a vacuum in the middle of the sponge, drawing in water from the sides of the sponge.