Oh man, I love the fact that you use mostly resin, as it makes your tank even more impressive. I would imagine you see the typical growth on the resin as you do on rocks; the tube worms, feather dusters, barnacles (small white dots), coralline algae of sorts, & maybe some sponges?
I always saw my rock as a nitrate factory, as they would just get loaded with detritus & I would have to turkey blast & suction them out when doing a water change. Years ago I did a little side tank with minimal rock & a medium sand bed & it worked out just fine, although the tank had only 4 small fish & sparingly fed & no skimmer and always wanted to take it to the extreme. I got that idea from a fish only guy that I met at a LFS in 2001, who told me he found the secret to keeping salt water fish & that he fed them very well. He kept nothing in the tank at all & no sump either. He vacuumed out the bottom easily & it made for easy maintenance, although it made for a very bland landscape. But he did his weekly water changes though.
1) Now lets push the envelope on the minimalistic mark. Do you think someone can have a successful SPS only or semi-mixed reef with only the rocks & plugs the corals came on & no other rock work. So nutrient export would be with the following:
-Water column
-Rocks & plugs corals came on (with bacteria & fauna) & whatever grown on the glass walls & pipes.
-The corals themselves, as they filter the water & absorb nutrients
-Over rated skimmer
-Carbon & phosphate remover if/as needed
2) Have you seen evidence of reefs that push this envelope of minimalistic to the extreme? Any links?
3) If you were breaking down your system would you wash the resin rocks with 1:1 vinegar:water or maybe Clorox & water...do you know what others have done?