I would not bother with the stage 1 or 2 filters (say 50 micron and 25 micron) and just use a larger 5 micron filter. The filter material is only about $8, so will last say 2,000 gallons? That is more than a season of camping, and should work fine.
Look for a replaceable cartrige filter holder that can accept 5 micron filters. It will filter out anything that you have shown, and probably if the campground wells has high iron, then it will take out a certain percentage of that iron, but not all of it. It will turn the filter reddish, and need to be replaced after visiting that campground.
My other suggestion is bring along enough water, and don't hook up. Or only hook up but leave the water off and use your pump for dishes and such, then the campground water for showers. Still this will fill the hot water tank with iron filled water, and I would suggest draining the hot water tank now.
To drain the tank, remove the plastic outlet on the bottom, and open a hot water valve inside to let in more air. If the stuff is really dirty, I would suggest connecting to shore water at home, and flush the system for a while.
Fred.
