Angelfish parasite? tumour?

Question
I have a community tank with 1 angel fish in it. Recently he/she developped a strange red growth on his upper lip. It's about 1cm/ one third of an inch long. I have kept angelfish for many years but never seen anything like it. He seems otherwise ok- normally active etc. Please do you know what it is and what I should do? Many thanks

Answer
Hi Victoria,
I have seen this before, and that was when my angel fish formed a couple.  They held each other by the mouth, and did the "Nuptial Dance" for quite a long time.  Cichlids do this as they must be of equal force to become a couple.  If this is not the case, then it could be a tumor.  It could also be an injury, from another fish in your aquarium.  Observation is always the key.  If she is eating, and looking normal, there is not much you can do.  If her condition gets worse, you could try a good antibiotic, such as Tetracycline, Furan 2, or Kanamycin.
Make sure your water is free of ammonia, and nitrates.  Ammonia in the water is the number one killer of fish, and brings disease.  Check to make sure you don't have any in your aquarium.  Do your water changes every week, and keep your temperature 78-80 degrees.  
If it is a tumor, she may live a long time.  This is not a parasite, and will not harm your other fish.
Hope this helps
Lynda