devil or midas

Hello, I have 5 red devil/midas mix cichlids for sale $3 each. they are about 4 inches and healthy. pickup in rockville or i may be going to the silver spring HS event.

Recently my red devil(or Midas whatever he/she may be) has developed a weird spot on his/her tail...kinda almost looks like a pimple actually...seems happy and healthy as its been there for about 2 weeks or so now and hasn't gotten any bigger...or smaller for that matter. Ive added an album in...