Got myself a breeder box today

Marina Breeder Box (Large)
http://uk.hagen.com/Aquatic/Misc.-Ac...Silicone/10943
What I have planned for it:
Will probably fill it with my black sand substrate I had in my old 10 gallon tank (just so I can easily clean and see the babies)
Will put in the pre-filter fluval sponge to be used as both a hiding spot and something to graze on (yay for dual purpose recycled material)!
and I will probably put some pieces of biomax filter insert pieces around there to provide bacterial growth and more grazing along with some java moss and maybe a marimo ball in there.
any comments suggestions or feedback is appreciated as always!
p.s: I am moving all my duckweed into the breeder box so I can remove my ugly straw border.