Tropical Angelfish

[Portia]

Hi, recently I have brought a large tank with lots of fish. One of the angelfish has a weird pink lump about the size of a pea maybe a bit smaller underneath it's bottom fins. Does anyone know what this is?

Thanks

 

[fluttermoth]

It could be many things; a tumour or even a prolapse.
 
Any chance you can gt a picture of it?
 
Also, could you post the size of your tank, exactly what fish you have and the results of any water tests you've done? Many fish 'diseases' turn out to be environmental, so a good description of your set up will help us determine what's wrong.