Tony,
As for your post regarding proximity of macros and SPS, I found that interesting, and it's something that I had forgotten about. Thanks.
I agree, macro algae harvesting (as in throwing it out and
not feeding it back to your fish) is only one part of the equation.
Randy mentioned that skimming is another one, and for some of us, the only real means of nutrient export.
One problem with using a protein skimmer is that the suspended detritus/DOC's actually have to make it to the skimmer in order for the skimmer to do it's job. In a high energy, SPS reef/bare bottom set-up with tons of water flow and turnover it's not so much of a problem, but if you add a DSB, densely packed rock piles and some LPS, all of a sudden you have areas of low flow where detritus can build up and cause nuisance algae problems over time.
You could have the best skimmer in the world, but if you have low-flow-only LPS, the detritus will build up and never get to the skimmer. That's where macro algaes could help out, I think.
Just for fun, I tested the P04 in my skimmate. 10ml of skimmate in 1 liter of water showed a reading of .25ppm. That's what, 25ppm P04 skimmate...
Glad to get
that out of my tank!
Mitch