Rummies are sensitive. I don't know if you drip acclimated them, if not that might have been part of them being shocked.
I would keep testing water. Do weekly PWCs and wait at least a week or 2 before adding new fish.
110L = 29g.
Don't change out filter pads...just rinse in used tank water or conditioned tap water. Re use till they fall apart.
What kind of substrate ?
Cories are one of my favorite fishes.
The common species are the easiest to keep usually. Pandas are more sensitive. But C aeneus ( bronze Cory)
, C trilineatus ( sold as C julii or false Julii) are great.
Just research before you buy.
Add slowly. I'd get 3 Cories ....wait... test water...watch fish. In a week or 2 add 2-3 more.
Do your homework. Don't pick something on looks alone. Rummynose are usually added last to a well established tank. So keep an eye on water quality.
Research adult size. Emeral "Cory" are a Brochis splendens that get larger than most Cories.
You could also look at C habrosus. They stay an inch and love planted tanks. They are more sensitive than the big Cories, but very hardy once they are established. Since they are tiny you could probably do 8 of them.
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