Cichlid Problems :(

Hey guys and gals i have a long story now about health problems in my tank...
about a month ago I bought 2 oscars and a pleco. put them in the tank and after about 4 days i noticed the Red Oscar was lying at bottom of tank not eating or swimming.
Eventually I managed to diagnose 'Hole in the head' from lots of research so I put him into a hospital and dosed with Metro, at the same time I dosed the tank with metro.
Then after a week he was happy again and I added him back into the tank.

Then my fish got Ich, not sure if its because I didn't filter the metro out, so I added a bunch load of carbon and rasied the temp to 30 for a week and fed garlic.
The Ich was gone

Now I wake up this morning and check a weird white pimple in one of the small severum's nasal passages...
Have done some searching and idk what it is...what could it be worms? fungus?

Should I leave him be for a while to see if we can make a better diagnoses?

As we all know how easy it is to photograph fish...here some photo's are, I realise it might look a bit like cotton wool fungus, but ill just watch like a hawk to see if it develops...but i don't think it is cotton wool.









Thanks the for the help in advance

 

Can you please use the Identifying disease questionnaire? This will help everyone to help you better. Thanks.

http://www.tropicalaquarium.co.za/showthread.php?6393-Identifying-Disease-Questionnaire