which species dwells in the nicest tanks?

[cichla81]

I'll agree with those but I am also going to throw in umbie's and dovii. Primarily because the people that purchase them "usually" know their requirements. They are generally housed by themselves as well, maybe not intentionally but it usually works out that way in the end.

i havent seen a bad umbie tank.

 

[TTTT]

Discus, fahakas, rays, and arowana usually have nice tanks.

Also any fish that is expensive is less likely to be purchased by someone who has no fishkeeping knowledge, so I see expensive fish having nice tanks, and cheap ones having unheated crapholes