ok I hate rocwool, or at least the type I have the package says you only need to soak them for 10 min in properly ph water and they will be ok , well thats BS,they constantly cause minor ph fluctuations nothing life threthning to my plants but annoying, so can I use sponges cut to fit my application, I know the pods in the AG use sponges, any ideas or recomendation on the type to get???