28g nanocube frag tank

[ONEmorBEER]

I picked up a 28g hqi nano cube and I would like turn it into a frag tank. I want to know what would work best for filtration. I am contemplating on filling the back with rock rubble. I am also contemplating on weather or not to use a sandbed. I was planning on making eggcrate racks with pvc legs. Does anyone have any suggestions on how to make this a successful DIY for me.

Thanks,

Chris

[JSE]

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