LOL..that was a fast reply...

With your bala sharks...are you aware of how large they get?
I know some will tell you they only grow as large as the tank
they are in..or that they will only be around 6 inches...not so.
I have seen Bala's that were around a foot.
Since these are fast swimming...and love to school in groups..
a tank of at least 75 gallons is needed eventually.
I know when I worked at the the LFS..we had people bringing them
back in all the time because they just got too large for their tanks.
With your little gourami...if it is still eating....
try soaking some flakes in garlic juice. ( smash a piece of fresh garlic).
This won't hurt the other fish either..in fact it is great for their immune systems.