Are 3-spot Gourami's aggressive?
The Three Spot species of Gourami is also commonly known as the Blue and the Opaline Gourami, and comes in variety of colours and patterning. The three-spot Gourami derives its name from the dots along its midsection, which if you include the eye, gives the appearance of 3 spots.
Most three-spot Gourami's remain peaceful as they mature, but some will become semi-aggressive and territorial when breeding. Keeping in small shoals, or with similar-sized Gourami or robust Barbs will limit any aggressive behaviour.
To avoid aggression towards spawning partners, housing with more females (2-3) to every male will limit any over-excitedly harmful behaviour from the males.