not feeding enough was probably the issue. LPS and softies like 'dirtier' water. I have a whole mixed bag in the tank I run the scrubber on. So far I have found that hammers, frogspawns, and dendros and for some reason ORA Green Birdsnest seem to retract toward the end of the algae growth period. However acans, cabbage leather, toadstools, colt, red cap, tri-color valida, war coral, candy cane, yellow polyps, ricordea, green digitata, trumpet, anemones, and especially mushrooms love the tank. Waving hand and xenia grow like nuts. Zoas seem to be hit or miss. I have one colony that has completely covered a large rock, and 3 others either slowly growing or holding their own, and one more that is just hanging on.
your observation about 'too clean' could be an effect of the screen being oversized in relation to your feeding. If you went be the old sizing requirement (tank size) instead of the new ones (based on feeding) your algae would turn yellow on the screen after it pulled all the N and P out, and yellow algae does not filter as well (although it still filters, it's just spread out over too large of an area so it's 'choked off'). This actually may be what happened to my tank, because that's where I'm at right now (yellow growth) and I'm getting ready to replace the oversized scrubber & screen with one appropriately sized for the feeding.
I also have noticed that since there is not a lot of algae in the tank to feed on, the reliance on a CUC seems to be less necessary. I try to focus on substrate dwellers and small 'nook and crannie' snails, and much less on the plowing Turbo snails as there just isn't a need for the size of crew that most suggest. I think some would recommend a CUC for a 144 of something like 300 snails and hermits and I bet I have 20 all together (and no algae problem in the tank). granted I'm planning on adding more, but not a significant amount.
