Cyst like lump on head

[Paddy]

Ive noticed this lump on one of my koi this morning, to be honest i have no experience with this type of thing, dont know whether its a cyst/ulcer or something else, the fish is behaving normally and the other fish are fine the water quality is very good and the pond is at 19 degrees, so im at a loss what to do, any advise please.lulu 2.jpglulu 1.jpg

[john1]

Hi Paddy, as its red looks a bit infected put some anti bac on it and see how it goes,repeat often.

[Paddy]

Im not sure John what to do, the skin isnt broken so would anti bac do any good? i sent Paula the photos Monday and fair play to her she replied and said with out examination she could'nt be sure, she suggested leaving it and it might drop off and that will be that, ive done a bit of researching and came accross Dermocystidium which from the description looks similar, i dont want to mess with her yet as ill be finished my quarantine in 2 weeks and providing it dosent get any worse id like to leave her alone, with her size she's a difficult fish to handle so its gonna be a mission even getting her out of the pond