IMHO C0 coral sand would be ideal (though Amid may disagree on this
) as its fine enough for sandshifters even as well as clean look and good buffer. Also, can use that tray/s (OHF) supposingly use for coral chips to put bio-media instead.
Note: Diff sources has diff grades of C0...some would be finer than others...from my experiences of purchasing 20~30 packets of 10kg of C0 in the last 24 months.