Red Spot On My Angel Fish

[ricci427]

Hello all,

I have a 30 gallon tank, nitrate and ammonia at zero, and ph round 6.5

stocked with
two angel fish quite large.
2 tiger barbs
5 neon tetras
3 sword tails
1 small cat fish
1 algae eater

i havent added any new fish recently, and do tank changes mybe once every two months, its a planted tank which help keep everything clean.

The larger of my to angel fish (I have had these two angels in for about 6 months), but the larger one has a small red spot on its side, behind the gill, wonering what it is and what i can do to treat it.

Thanks for any help you can give.

 

[WILDER]

Does the red spot have any whiteness around the edges or a white centre.
If there no flicking and rubbing I would go in with a bacterial med.
Can you issolate the fish for treatment.