20 gallon high

Pygmies are almost not bottom fish, much more low midwater swimmers.

It's the temps that are different for some of your fish. Bettas, cardinals & rummies are good at 79-80F-ish. Sterbai corys, rams, apistos & most kuhlis too. But for pygmaeus, clown plec & shrimp that's pretty high. It's not that you can't but they may be slightly stressed, more prone to disease &/or have shorter lifespans.
 
I’m not doing well pygmy corydoras anymore. Still trying to figure what to get. Did some quick research and the clown pleco and amano shrimp can handle 78-80° water just fine. I had the amanos for nearly 2 years at that temperature in other tanks and same with the clown.

Thinking this stock list for now, tank is over filtered with weekly water changes of 25%.
GBR pair
8-10 cardinals
6-8 kuhli loaches
Clown pleco
4 amano shrimp
 
What kind of heater is that? Mine (aqueon?) has warnings all over that it must be horizontal or vertical. Not in between. Been having issues with them lately.
 
After waiting a awhile I added some fish. I added 6 neons(couldn’t find cardinals that weren’t ich covered) and a trio of blue rams and endlers. Had them a few days and they are eating anything I put into the tank. The rams actually come to the surface to eat, usually I don’t see them do that and are always out and about. B0FAF8E1-50CF-4502-ABB9-23E119AC3842.jpegEF4925C2-E4D0-4A0C-BAA2-AABCBDDED51E.jpeg387C4FB3-28E2-4A24-BE6D-11C7C01C8E8C.jpeg
 
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