Welcome to AA ... glad to hear the site was able to help you. A bowl is probably too small for a Gourami ... depending on which one, they can get up to 6 inches.
Yes Gourami's can be territorial and aggressive, even to other Gourami's.
You can return it to the fish store it was bought ... or ... as I just did .. call a local trusted fish store and ask if they'll just take it. I have a 3 inch Blue Gourami that is quickly becoming the tank bully ... seems to get bolder and bolder every day .. and it can still grow another 1 - 3 inches.
75g Planted Barbs Denison, BlackRuby, Tiger, Albino Tiger, Green Tiger, Cherry, Gold, Checkered, Odessa.
NonBarbs Cardinal, Neon, RummyNose, Bloodfin Tetras, Z. Danios. 1RTS. Amano, Bamboo, Ghost & RCS. 20g Long Shrimp Tank RCS, Tiger, Amano.