Best Temperature For Cory Catfish & Neon Tetras

I recently bought a new heater that is adjustable and after reading some threads on here realized that the temperature of my 20 gal probably needs adjusting.

In it are 4 neon tetras, 1 albino cory catfish and 1 emerald cory catfish.
I will be increasing their schools next month.

My question is, what temperature would make this tank happiest?
I read some cory catfish prefer lower 70s and that the neons should be around 76 but just want to know if 75/76 the best temperature?

I was also considering adding a dwarf gourami and some guppies later on, so need to take them into consideration of whether they'd be happy in colder waters

 

can you place a pic of the emerald ?

 

can you place a pic of the emerald ?

He's the funniest thing bc when we first bought him he looked like an albino, and when he first changes tanks he's super light. But then he darkens. I'm not 100% sure if he's an emerald but that's what the store listed him as (got him from petsmart so I don't fully trust that). Photo of him in the bag is when we first bought him.

 

Ahhh just what I thought. It is a green C.aeneus.
Official Emeralds are Corydoras Splendens, which need warmer water. Your (beautiful) fish has a wider temprange than Splendens.

 

Ahhh just what I thought. It is a green C.aeneus.
Official Emeralds are Corydoras Splendens, which need warmer water. Your (beautiful) fish has a wider temprange than Splendens.

Google. Shows that as a bronze, did that mean that in some sense they're the same class? (I was told bronze and Cory are the same but I'm clueless hence me asking).

Would they be happy/happier around 76?

 

Google. Shows that as a bronze, did that mean that in some sense they're the same class? (I was told bronze and Cory are the same but I'm clueless hence me asking).

Would they be happy/happier around 76?

I keep them unheated.

This one almost looks like C.venezuelanus btw but I think those are used to get this colorvariaty.

 

Gotcha. I don't know how well the new house were moving to holds temperature so I'll probably keep a heater until I know how it does.
When buying more, should I still get 2 more bronze and 2 more albino or will they school together regardless?
I probably will regardless just so no one feels left out

 

Gotcha. I don't know how well the new house were moving to holds temperature so I'll probably keep a heater until I know how it does.
When buying more, should I still get 2 more bronze and 2 more albino or will they school together regardless?
I probably will regardless just so no one feels left out

Those are all the same species so no problem.

 

I'm pretty sure Dwarf guaramis need warmer temperatures. I keep my tank between 76 and 78 but have a wider range of warmer water fish. My neons do fine in the warmer water though so if your Cory does need warmer temps your neons should be ok.