+1 to eggrate with PVC legs or construct an eggcrate box with zip ties to fit nicely into that compartment of the sump.
isnt there a debate on whether egg crate adds phosphates to the tank?
I use egg crate with 2" PVC legs in my 100 gallon stock tank but I have a 12" diameter skimmer that weighs a lot when full so it doesn't move around.
Why raise the skimmer for? does it do anything good for the tank?
Depends on the skimmer and water levels in your sump. Some skimmers will perform optimally at certain water levels. If the water level is too high in the sump, you can raise the skimmer to its optimal water level.
I didnt know that!
Does the ASM skimmer requires that? Just wondering.....