1. If you have a protein skimmer you should shut it off when you are adding medicine to your aquarium. The protein skimmer will remove any medicines added to the aquarium.
2. Angelfish are normally very peaceful fish, in times of breeding they can get aggressive. It is a good idea to only keep one pair of mating angelfish in the same aquarium, as more of them can lead to infighting.
3. In larger aquariums, you should put a few scavenger fish in the tank. Scavenger fish will help to clean up left behind food and wastes from the other fish in the aquarium. This is a good eco friendly way to keep your aquarium clean.