Barb and Bala shark friends????

This is the weirdest thing, my bala shark is usually very skiddish with most of the fish in my tank....except for one small albino barb 1.5". They stay together all the time and i have occasionally caught what looked to be the barb cleaning the bala shark....i assume this because the bala shark will float motionless and the barb will carefully nibble right above where his side/bottom fins attatch to his body and right on his belly and he does it quite methodically (one side then the other) i would assume if he was nipping at the bala shark that the bala shark wouldnt sit there motionless and let him do it...but what benifit could the barb be gettin out of it to motivate him????

this doesnt seem normal....do barbs usually "clean" other fish??

Ya that sounds just like it!!! the bala shark points his head down and just hangs there motionless....im wondering if its because he is the only small albino barb in my tank, I have 3 green barbs 3.5" and three tiger barbs 3.5" and this one is all by his lonesome at 1.5".

Ya it is cool to watch....because he cleans the Bala shark soooo perfectly...picking at one side then moving to the other. I was gonna move the Bala shark to another tank with out the barb but i just dont have the heart to do it beacuse they like each other!

Also what do you think he could be cleaning off of the Bala shark??


PS I have a digital video camera and he does this all the time...so I'll catch it on video and let yall see the weirdness!