It is probably possible but would be rather difficult. The only way of converting the sump to a refugium is to use the first compartment as the refugium then covering the pass-though holes/dividers by gluing in a couple of acrylic sheets . It would also be a good idea to add an additional plate to raise the water level in the first compartment. Unfortunately, we have no idea of how well it would work out. Using a CPR AquaFuge would probably be much easier.
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