Is this good advice for stocking a tank?

[Sutster]

I've been slowly stocking my 20 gal. long. Right now it has;
4 long-fin leopard Danios
2 Skunk Cories
2 Emerald Cories
3 Neon Tetras
3 Neon Black Tetras

The reason I have 3 neon and 3 black neon is I wanted to finish my tank with 6 neon tetras and I lost 3 due to being sick from local pet store. I waited watching my other fish went back and the employee told me to stay away from the neons and go with some black neons. (should of done my own research like i usually do).
So, I want to fill out some schools and I'm getting another whisper 20 filter so I'll have two whisper 20's. During some research I found an (Intelligent Aquarium Stocking Calculator) at AqAdvisor - Intelligent Freshwater Tropical Fish Aquarium Stocking Calculator and Aquarium Tank/Filter Advisor. I attached my dream team stock load with two filters and this stocking calculator is saying that it is still at 89% filled. My dream stock of fish is way too much, right???

 

[Fishperson]

Yeah, that's too much probably, but not by much. Are you able to get rid of some of the fish you currently have?

 

[Sillyfishies]

I've been slowly stocking my 20 gal. long. Right now it has;
4 long-fin leopard Danios
2 Skunk Cories
2 Emerald Cories
3 Neon Tetras
3 Neon Black Tetras

The reason I have 3 neon and 3 black neon is I wanted to finish my tank with 6 neon tetras and I lost 3 due to being sick from local pet store. I waited watching my other fish went back and the employee told me to stay away from the neons and go with some black neons. (should of done my own research like i usually do).
So, I want to fill out some schools and I'm getting another whisper 20 filter so I'll have two whisper 20's. During some research I found an (Intelligent Aquarium Stocking Calculator) at AqAdvisor - Intelligent Freshwater Tropical Fish Aquarium Stocking Calculator and Aquarium Tank/Filter Advisor. I attached my dream team stock load with two filters and this stocking calculator is saying that it is still at 89% filled. My dream stock of fish is way too much, right???

Emerald cories don't belong in 20Ls. They get BIG.

 

[Sutster]

Emerald cories don't belong in 20Ls. They get BIG.

The Local Pet store sells these as "Emerald or Green Cories", but there is something about the dorsal fin. I'm a newbie at this, is it a different Cory, maybe a Bronze?

 

[Sillyfishies]

The Local Pet store sells these as "Emerald or Green Cories", but there is something about the dorsal fin. I'm a newbie at this, is it a different Cory, maybe a Bronze?

Looks kind of like an emerald cory. Emerald cories arent even corydoras. They're bronchis.