I'm not saying they can't, just not something I've ever seen with mine or in any research I've seen. There's several species that are often listed in the LFS
, so there's no telling exactly what it is without further research. Thanks for letting me know though.
Assuming it's a 20H and not a 20L, I would say there is some room for a centerpiece fish, a small gourami or even a small school of dwarf corys.