Molly With Pepper Size Lumps

[kalahari]

Hi folks

My daughter and I have been running an aquarium for about four years now, with very few problems. we still have the first fish we put in – a red tailed shark called Luke. We also have a thriving community of mollies, but tonight we noticed that one of the males, a black, about 10 cm long, has a mysterious peppercorn sized/shaped lump just below its dorsal on the right flank. Any thoughts? Is there a danger to the other fish? I've not seen anything like it before.

Thanks, kalahari

 

[WILDER]

Size of the tank in gallons or litres.
Water stats would be good.
Does the lump look like a cauliflower.
What colour is the lump, does it look hard or like its filled with liquid.
Is it possible to get a pic up.