Another "too much foam" thread

What gives? Only one of my two kegs is over foaming and I can't figure out why. It has 5 feet of hose, is chilled to 42 deg and is serving at 7 psi. My other drink gives a nice bit of head and serves very well. I did have the foamy keg shut off from the gas for 6 days... would that contribute to excessive headiness? I tried purging and re pressurizing, but that didn't help. Anything I'm missing?
Thank you!

check your o-rings and reseat the poppets.

I had a problem with retaining too much foam for a while. but before I get into that issue first increase your tube length to 10 ft of 3/16. the calculations that most people use seem to be incorrect. last night I changed from 5 ft to 10 ft of serving tube and the foam problem was drastically reduced. Now I can fill a glass in one pour instead of three. the other problem might be too much protein in your beer. I realized this when the head never dropped and the head appeared tough(?) like the scummy foam you see on the beach or in a salt water aquarium without a protein skimmer(this is where I got my idea). Since then when doing my boil as the foam tried to boil over I use a strainer to scoop the foam out and discard it. I don't lose any volume and it hasn't seemed to affect my gravity. I do get a nice head of of foam, but it is a soft, creamy foam that leaves a beautiful lace on the glass and dissipates appropriately. I protein skim all my batches now and it help give me a cleaner product that I can be proud of.
your pressures and temp seem good.

I don't think I'll be switching up to 10 feet too soon, but I did go through and re-lube, and tighten everything. When I opened up I did notice the the beer itself has a lot of foam on top. What might this be caused by? It is nearing the end, and that seems to be a common point for my beers to get really foamy. Any advice?