fungus / growth id needed on plecs

[matt123]

Ive recently lost two of my largest plecs in my 200 uk gal tank i thought it was just coincidence as both of them were ancient and had been together since little.
today i have noticed a weird fungus or abrasion growth on another of my pecs in the same tank,
none of the other fish are affected as its a large community and all my water parameters are reading 0 on no2 + no3 Ive been doing steady 30% water changes every other day since the loss of my other two as a precautionary.
can anyone guide me in the right direction for medications and as to what this fungus is most likely to be ??

photos attached show worst affected area which seems to be the main bone on the pectoral fins but there are small batches towards its tail.
thanks in advance

 

[BODYDUB]

Looks like he's been rubbing on something...........

 

[matt123]

ok so the fungal infection has got worse and is now hitting all my plecs, please can someone identify what this is most likely to be as i need to treat it before it wipes out my tank as it seems to be spreading to my cichlids aswel heres some updated pics, as you can see its really tearing into them at some speed so i need it identified asap
thanks again

 

[Lupin]

Fungal infections are very rare. Unless the plecos have been rubbing to the point they skinned themselves and the wounds are left untreated, fungus is not the issue here. Fungus should exhibit white cottony growth. This is bacterial to me if all your plecos are hit.

Did all flash?
What are your water parameters?
Tank size?
Tankmates?
Fitlration?
Maintenance schedule?
What antibiotics do you have access to? If you are going to mention Waterlife, Interpet, etc, please include the active ingredients as well.

We need more details.

 

[matt123]

thanks lupin

i havent seen any of the fish flashing
all paramaters are at 0 for amonia, no2 and no3 and ph is stable at 7.0
tank size is a 200 uk gal
tankmates are 2 oscars, green serv, 2 lemon fin barbs, pangassius sutchi, GT, and a striped pim with the 3 plecs (1 large 2 med)
filtration is a custom sump and an large external cannister combined flow rate of 1000 gal ph
maintenance schedule is a 30% waterchange weekly and filters cleaned every month if flow is restricted
i have access to any meds as i work at a decent lfs so thats not a problem i just wanted to know what route of treatment to go down.
(sorry if ive repeated myself in this post from my first one but thought it would be better to have all the info in the same post)
thanks again

 

[Lupin]

Very odd for your nitrate to remain zero considering you keep plecos and plenty other large fish.

Did you conduct this test before or after a water change?
What test kit do you use?
Do you use anything that reduce nitrate such as Seachem Matrix, denitrators?

These are not fungus. What meds do you have access to that are antibiotics?