My 300 gallon Drop Off Reef Tank Build

[sphelps]

Only issues I see with leaving that space accessible is it resembles a invert trap, craps, snails and shrimp may not find their way out after getting in. It also maybe a dead spot for flow and lacks proper access for cleaning which could become a source for issues down the road, ie livestock could die in there or nuisance algae could bloom from there.

Love the idea though, but personally also think your stand it too high for this style of tank.