greasy film

[mnjr12000]

i have a pool with a heated spa attached. i do not have a problem in the pool. but when i use the spa a greasy substance forms on the waterline and floats in foam in the corners with little waterflow. i drained spa and cleaned grease line, but it reappeared. when i use the spa the water circulates from spa to pump, filter and then heater and back to spa. when i am finished using spa the water then flows back into the pool and recirculates thru entire system, pool and spa. i just dont know where this is coming from. could it be a buildup from suntan oils and body oil that is in the pool system and starts to move when water is heated or something else. if so how do i get rid of it? my pool and spa is 1 yr old

[dynamictiger]

It would be helpful to know what your water parameters are.