
Me too.
I believe the red color comes from rusty iron.
Speaking of yuck, I've been using a skimmer on my 200 gal coral farm system for the past 8 months. Because of multiple soap and sunburn catastrophes where I lost almost all coral (several times), I'm reminded of how yucky the skimate can be. "Skimmerless Mark" may never be skimmerless again,

at least on this system.