on a 30 gallon I wouldn't worry about it, if its glass...I have nothing under my 46 gallon bow front, and I have 40 pounds of sand and 50-55 pounds of LR, plus whatever rocks I get corals on now, the sand keeps the rock from putting all its force in one spot if they are not totally through the sand...people do use egg crate on the top of open tanks to keep fish from carpet surfing.
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...AGA 46 gal. bowfront, coralife 192watt aqualight, koralia 4, aqua c remora w/maxijet 1200 and surface skim box,200watt heater, 40 pounds black aragonite reef sand, 50 lbs. LR...cycling at the moment...
...12 gal. Nano-Cube, heavily modded, becoming a QT/Hospital tank for the new 46 |