Looking at the photos, your tank is not crowded at this point, but that's because all the fish are basically juvies.
Once they reach a semi adult stage, and your nitrates start creeping into the chronic HITH range (of over 10ppm), a thinning of the herd will be the name of the game.
If you keep all, and all were able to reach adulthood, daily 80% water changes will be needed to keep up with the bio load.