Okay, I respect that. You admitted you messed up and you are fixing it. Maybe you ain't so bad. Just make sure you actually do follow through on it though...
You could probably keep one or two of the Hoplos if you amp the filtration up a bit.
I'm pretty sure Snowflakes are brackish so its not gonna live a good life unless its in brackish. I would put it on the rehome list as well. I know its sucks when you spend good money on a fish and later have to give it up.
The people at the fish store said that the eel was as big as it was going to get and it was fully fresh. I know them personaly and they wouldn't lie just to sell me something. I'm going to try a keep my HD because he is not very aggesive.
Walmart sells "freshwater" puffers and gobies so it doesn't mean they are. I know a pet store that believed you can keep parrots fish in 5 gallon tanks, doesn't mean you should.
They may live in your freshwater tank but they prefer brackish water.