Aggressive Gourami
David, Aside from the possibility of Darwinism being part of this problem, as Lenny points out, and aside from this fish being in an undersized tank for its eventual full size, it can be expected of any variety of the Blue/3-Spot Gourami (Trichogaster trichopterus), including your variant Opaline (Cosby), to be aggressive in their behavior as is well known for this speciesas it being one of the more aggressive of the Family. While some other Gourami’s can be somewhat aggressive, this behavior you’re experiencing also bodes well unfortunately for the Gold and the Platinum (or Silver) — not to be confused with the Moonlight Gourami — Gourami’s, other variations of the Blue Gourami (or “3-Spot” Gourami).
While a larger (20 to 30 gallon) tank would be more in line with the requirements to maintain it, this will not necessarily reduce its tendancy to display its innate aggressiveness towards its tankmates, especially those smaller than itself. Possibly, about the only type of bottom-feeding fish you could keep with your Gourami that it would not kill might be an Electric Catfish, which should be able to hold its own against this marauder .
Since you’re limited for room, I would recommend that you trade this fish back to the LFS (or give, if need be, if PetSmart won’t otherwise take it), and purchase something more peaceful. If you prefer this general type of fish, try a Dwarf Honey Gourami as its peaceful and more in line with the size of your tank. Ray
Category: Philippines Internet Koi Society
