Think I figured out why my tank was crashing...

[Aquattro]

Mason, that's a question just dying to be answered. I was just doing some reading this morning on over-skimming. A lot of conflicting opinions out there. I can't make sense of them all ;)
I use a skimmer that's way too big for my tank and I have tons of critters in my tank. I have worms, mysis shrimp, the usual assortment of amphipods/copepods and things I can't identify. Microsocpic examination of my skimmate doesn't show much in the way of critters, so I assume they stay in the tank.
Will a skimmer remove some of the DTs? Certainly. But the cost of 0.5 ml loss of DTs to the skimmer isn't worth the accumulation of dissolved proteins that the skimmer removes. Having a skimmer also promotes better light penetration by removing suspended particles.
Having said that, after a recent move and resultant increase in dissolved organics, my corals have never looked better. This is suspected to be temporary, but shows that the corals do like something that is normally skimmed out.
A fellow hobbyist in Victoria has run skimmerless for a long time, however, he now finds he has an algae problem that is getting out of control. He feels now that a skimmer is required. (*Mike, call me about your skimmer).
In the long run, I would personally use a skimmer and buy/feed extra phytoplankton. Worrying about a skimmer removing it doesn't justify not having a skimmer. Remember, this is just my opinion and what I have found works for me.