I would knock off the blood worms and go to frozen brine shrimp. Blood worms, mysis and formula 2 are all very rich foods. The fish can use some of whats in the brine and its not so rich in nutrients. Also, don't shred the nori, attach it to a rock or clip in one piece. That way little pieces are less likely to get stuck behind a rock and not get eaten. You could use some critters in there for clean up. Little mexican blue legged hermits will really consume cyano. Reeftopia has them for a good price. I have tanks full of goldstripped maroons at the rate of 1 fish per gallon without skimmers and with only 10 very small astrea snails and no cyano so I will have to agree with your LFS on the skimmer. But, perhaps my O2 level is higher than yours. Good R/O water, good brand of salt and R/O for top off water should not create excessive algae. Its been reported that the bottled water from HEB is high on TDS. Are you sure the Ozarka is R/O? Double distilled isn't good. It will be interesting to see what that bottle tests out on Saturday.

BTW, sand sifting stars will not hurt the sand bed. They consume algae and detritus by ejecting their stomach linings and then absorbing nutrients. That method is too slow to catch any of the fauna in there. When they are moving, they aren't feeding.