got a 35 gallon pond

White cloud minnows

Gambusia (mosquitofish)


Fathead minnows

Pygmy killifish
 
Do you have one of those black 35-36 gallon patio ponds?

I have one of those.
 
I've kept mosquitofish in there with good success.

Any small tropical should do fine.

I would try white cloud minnows.
 
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