I have a Blue Gourami (Golden) and his behaviour has changed a little of late. He would always have a little scrap with my Dwarf, but since the dwarf passed away, he has been very lethargic, choosing a few favourite spots, and just sitting still.
More recently, I noticed a red-brown spiky looking bulge at his anus, like a tiny rambutan. Not sure what it was. I was there sometimes, and sometimes not.
Last night I was watching my fish for a while, and noticed what to me was very strange behaviour.
The Gourami was going vertical (Like my headstander), and my Rummy Nose Tetra, were picking at his anus...purposefully, and the Gourami appreciated it.

In fact whenever the Rummy Nose swam behind him he would immediately assume this vertical position! It was like a symbiotic relationship. The Rummy nose would not eat the poo, but appeared to help it out. It is not just one of the Rummy's, both do it. Is the Gourami constipated? And how do the Rummy Nose know to help him out? Bizzarre.
Has anyone seen anything like this before?
Fish are fed 70% tetramin flake, 20% Shrimp pellet, 5% Algae wafer, 5% Dried bloodworm. Water changes are about 30% weekly. Aquarium info up to date.