The fish at the bottom are (or used to be) P. loiselle. The names of that species and freidrichsthali have been changed—not sure what the latest “final” decision is.
Tank size depends greatly on fish age and size. I bought RTM fry about 16 months ago and now have 3rd generation fry in a 55gal community tank. (Pics are two different motaguense mothers with fry, and one doesn’t have much color).
My favorite fish are the Harlequins, or Red Terrors, especially females. (Pics are a pair of 6-7 inch fish, by themselves in a 55, currently with about 200 fry).
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