Horizontal inserted into a face board that has 3 holes cut in it. Inside each pair of socks will be several plastic rings to keep them open. The tail of each pair will be tethered to the end of the run to keep them from contacting each other.
Right side first array in example:
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No water can bypass the arrays and there will be a 200 micron prefilter in the intake before the water enters the first arrays.
The sump is essentially siamese twin sock filter/scrubbie filters that share a common intake and pump chamber. The intake is sort of like the leaf intake on a swimming pool, except it won't allow anything that big in.
The pump chamber will contain pumps for the 4 12 gallon canisters and the return pumps back to the tank. The return plumbing for the sump pumps will exit at pretty much the same level as the pump outputs and will have eductors on the ends to increase flow in the tank.