Soil-free wheatgrass grower reccomendation?

Hi,

I'm looking at soilless grower systems, the ones that stack up in levels, preferably with the possibility to get coevered (i live in a flat, so it would be nice if i coul keep them on one of the balconies most of the time (one is open, the other closed).

Something like this i suppose


http://www.discountjuicers.com/wheatgrassgrower.html


except that the only review of it is a screaming "MOLD MOLD MOLD". It could be the guy using was doing something wrong, but i don't know. Anyway, if anyone is succesfuly using a soiless grower system, please tell me which one it is.

Thank you Tweet