Pink/red Lump On The Side Of The Angelfish, Behind The Gills

[TomShootsPhoto]

Hello guys and girls...

:'(


I've been having a lot of problems with my tank lately. And today, this.

About 15 minutes ago I noticed that my angelfish had a red/pinkish lump on it's side.


Pictures:
http/imgur.com/a/DQvU8


What is it? The tank is: [background=rgb(252, 252, 252)]300L tank with 4 cory cats, 1 Angelfish, 2 clownloaches, and one Bristlenose pleco.[/background]


The temperature is around 25 C, 77 Fahrenheit.

Water stats are normal. (7.6 PH, 0ppm ammonia, 0ppm nitrite, 0 ppm nitrate)

What could the problem be?

Sadly, none of my LFS sell medication for fish. The only LFS that does is closed for the next 3 days because they are rebuilding.

Thank you for your help!

 

[techen]

Water stats are normal. (7.6 PH, 0ppm ammonia, 0ppm nitrite, 0 ppm nitrate)

Pretty sure you should have atleast a tiny bit of nitrate no?

 

[TomShootsPhoto]

Nope, none at all.

 

[techen]

Nope, none at all.

How long have you cycled the tank for?

 

[TomShootsPhoto]

It has been cycled for for a long time, over a year probably.

 

[TomShootsPhoto]

Can someone please help?

 

[TomShootsPhoto]

Anybody? :'(