yours has some really nice looking plans to it.
a couple of thoughts.. instead of individual maxis, you might be better off running a larger pump on a manifold- that is split out. I think your wattage will be less, less heat, and you won't loose as much flow and energy fighting the head-loss. With that said- the Maxis are a perfect acceptable way.
Also, is there any way to divert your skimmer return to the sand bed part? Chaeto will do better with more dirty water, your skimmer output will be the cleanest spot in the tank. you DO want the sand bed to be after the skimmer though....
For now, my sump room will be a collection of tanks plumbed together. I am planning running my refugiums in a separate "modular" way- so i can isolate each algae/ stage etc. and give it the exact conditions it wants- similar to a partitioned sump like yours.
right now, I will have
-my chaeto growing in a 25-40 gallon bb, getting tumbled
-gracilia potentially in it's own (25-40 gallon) (potentially mixed with a few species of it)- it's conditions are similar to chaeto... but I want them separate for husbandry/ growth issues
-a remote DSB that will be in darkness
and potentially... (have to do some more research)
-a low flow dark area aimed at filter feeders
- a rubble section aimed at pod growth... this is potentially under the gracilia...
I have to balance the detritus that will collect in the rubble vs. the pod production potential it has.
all this will drain into the 55 gallon sump... nothing will grow in the sump- it will be a buffer zone for the temp, salinity, kalk, CA reactor dump, etc. if the sump gets too small, i convert it to a refugium and get a bigger sump
It sounds complicated, but it is rather simple in theory.. no advanced dosing short of Ca, Mag, Alk, from my calcium reactor... a stable mostly self balancing system (i will run carbon and potentially rowphas)
Big refugium system aimed at 30% buffering with no high predator bio-load, 30% nutrient removal, and 30% pod production) 10% just cause it will be fun
