You're going to need to keep your pH low (7.0-7.4), your chlorine low, and the metal sequestrant in the water. If you have the Culator, go ahead and put it in the skimmer--it won't hurt, and it may help!

I have zeo in my filter, just because I wanted to try it--but honestly I don't see any difference between zeo and sand when it comes to filtration--the zeo is more expensive but you have to haul less of it--that's the only advantage I see. Shouldn't make any difference one way or another with your metals situation.