lots of foam and a yellowish geen scum line

I refilled the hot tub added some metal gone,and calciumand scale preventative. I am getting lots of foaming plus a green yellow scum on the side. I am using well water which has some iron in it. The PH is about 7.8

[Mary]

Foam is usually caused by something being brought into the spa. For instance, detergents on swim suits, shampoo, body lotions, etc. What you can do is take a sample of your water to a local pool spa store. They will usually test the water free of charge and then give advice on what spa chemicals (http://www.hottubworks.com/HotTubChemicals/) can be added to clean it up.