Just remember to check the footprint of each skimmer and see if it will fit in one of the back slots. Most AIO's are only usually 3-4 inches deep in the back compartments. The AquaMaxx NF-1 and Tunze 9001 may not fit not fit. Not sure if you bought your tank yet or not, but if you have not you can always reach out to the maker of the tank you are looking to get to get the measurements of the back compartments. Then once you have those build out your equipment list from there.
Actually after looking on the Waterbox site I found the dimensions. The entire filtration compartment is 13.8 x 3.1 x 13.8, the filter chamber measures 3.1 x 3.1 x 13.8, then the skimmer chamber it 4.9 x 3.1 x 13.8, and finally the return chamber is 3.7 x 3.1 x 13.8.
So the footprints of the AquaMaxx NF-1 and Tunze should fit, just the magnet will be inside on one of the walls.
Anyways, happy reefing!
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