1. 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.
2. It is not a good idea to wash your filter media with regular tap water. The tap water can kill the beneficial bacteria that is built up in the filter. Use distilled water to clean out your filter and its components.
3. You should always stay up to date on the new and exciting practices for fish keeping. Subscribe to several news letters to keep up to date. If you like to read, go to your local library and get some books on fish keeping.