Cleaning for diease while fish still in the tank

So I have treated my 55 gallon for "Something" after I had 4 pacus, angel fish, a few mollies... To die... Then I learned of ich. Algae eater also died.
But I then removed my oscar, bought another pink Oscar and put them in tank 2.
Now tank 1 was treated 7 days and removed a lot(half)of the water... Remaining in tank 1 is 4 snails, 4 black mollies, 1 gold and 1 multi color bigger molly, (red) algae eater.
Now the snails been on some freaky ****.. The gold and blue snails ok then I learn they are unisex and can hold eggs until they feel its safe...Ok treated changed water put the filter back in let tank 1 sit a few days...
Then bring both Oscars in Tank 1... Now Tank 2 (30 G long) is an albino tank. So I was talked into tank 3... A 1G quarantine tank...
But now the Pink Oscar was acting funny... Maybe full but the original Oscar eat everything from it for. So Idk..
Now it looks like it has the ****.. On its fins.. So I removed him... Put him in Tank 3.
Then I go to google... And what I thought was baby snails... Actually might be.. Whats at the bottom of the tank?
Help me out??? I don't have a tank 4.. So Im guessing to remove the decorations and possibly clean them?? Then scoop the bottom out and remove some top water in a bucket with the fish... Then remove all water to clean the bottom??

Boil the gravel and then rise it and strain it?
Help!!

Hi and welcome to the forum

I don't mean to be rude but I am having trouble following what you wrote. Can you sum it up and just list the problems and what you did to try and fix them?

Post some pictures of the sick fish?

If you have water testing kits, check the tank water for ammonia, nitrite, nitrate and pH and post the results (in numbers) here.

@Kincaid did you figure your problem out?

From what it sounds like, you have 4 tanks: a 55g, a 30g, a ?g, and a 1g, is that right?

And over the past couple of weeks your fish have been playing musical chairs between these tanks?

Can you post what fish are currently in each of these tanks, and which of the fish are ill?

Post pics of the ill fish as well. We will try our best to help once we understand the situation better

Tank 1... 55G.. Oscar, Catfish, black mollies
Tank 2... 30G long.. Albino tank-
Tank 3... 1G quarantine..

Pink Oscar in quarantine now..

But tank 1 was infected with itc.. I guess.. Changed 65% of the water. Took out all the gravel. Added some back. Then new black rocks

But ya can see the white dots on the glass after I even changed the water and glass

Can I just say mollies and Oscars don't belong together.

White dots on the glass are not ich.
Do you have any nerite snails in the tank? Mine lay eggs which look like that.

What is the oscar in quarantine for? 1gal seems so very very small for an oscar for any amount of time...

Were you able to get rid of your ich outbreak? Are your other fish healthy now?