Behavior question - pecking at slime coat?

[ashlerolds]

This may be a silly question, but I couldn't find an answer searching the archives. The largest fish in my tank (4.5" red pigeon blood) is clearly the dominant one in the pecking order. All of the sudden he/she is laying sideways and allowing one of the other fish to peck at her slime coat. He/she actually seems to be enjoying or encouraging the behavior. I don't see any damage or other signs of illness, but this behavior is strange. It seems to be one mostly one fish in particular that is doing the pecking. I had previously thought the PB was trying to pair up with the other largest leopard snakeskin in the tank, but he is not the one pecking at her. Is this normal? Does it mean anything? Should I be concerned? Weird to see her laying sideways like that!

Tank parameters:

110 gallon planted (1/2" white crushed coral base, plastic plants, driftwood)
9 discus 2.5" - 4.5", 1 pleco
Tank has had discus for 6+ months = no illnesses or fish loss
50% WC every 1-3 days (2-4x weekly)
Well water with prime and neutral buffer added
T=83.5 F
Ammonia - 0
Nitrite - 0
Nitrate <= 20 ppm
Ph=6.8
Total hardness 120 ppm
Alkalinity = 180 ppm


Thoughts?

[Eddie]

It could be an organism is attached the fish and the other fish is pecking at it.

[Skip]

i have seen this in some fish i had.. i also asked same question..

nobody gave me a good answer.. nor had anybody really ever seen this.. so its not common but it does happen from time to time..

it did eventually stop happening. .

[Mgardner]

I had a rainbow shark that would eat at the slime coat of two of my discus, but not the others. I don't see anything on them... So I took him out. Didn't seem to bother them... Guess its kind of the same thing? I hadn't seen it before this week, though.