weird stuff on my oscar?

[ctenopoma]

my oscar has light coloured blotches on his/her forehead it only appears when it turns a certain way under the light, does anyone no what this could even be? it seems to have appeared over night.
sorry I couldn't include a picture.

 

[pcfriedrich]

could it be his slime coat? i know Os are known for having an especially thick slime coat. mine has a visible amount in the mornings, before it starts swimming around a bit.

 

[ctenopoma]

could it be his slime coat? i know Os are known for having an especially thick slime coat. mine has a visible amount in the mornings, before it starts swimming around a bit.

it kinda looks like oil/slime and seems to be changing shape

 

[mbunafishkeeper]

i dont think you have to worry about it my dad's O gets similar thing and has done for a while, it comes and goes and i think its due to stress from other tank mates.