Then ide really have to go with what i trust in that situation.
Different shaped marbles (shooters vs standard size) to create gaps, all poured on top of egg crate.
(I like to use dark colored, black even, marbles, easier to see the eggs IMO)
Sponge filter in the corner with a piece of tubing so that the bubbles expel a bit closer to the surface to keep current and agitation down to a minimum.
Also, i like to throw in a nice big pile of java moss, get it to float. (usually floats at the top of the tube from the sponge filter) aids in filtration a bit and the fish hang out under it for respite. Some even put their eggs in that instead.
Sorry i couldnt really help you find something new, but its a tried and true method.
Good luck with your breeding adventures be sure to keep us apprised.
-ChairmanWood