rockwool source

I am having problems with my clown loaches digging up my plants.  I want 
to start them in rockwool before planting to minimize the effects of this 
disturbance.  Pet Warehouse has the Hagen and Aq Products plant plugs.  I 
am not too impressed with the Aq. Products, especially since it is 
impregnated with AP fertilizer.  Is the Hagen stuff any better?  Is there 
a better, hopefully cheaper alternative?

Thanks in advance.  TOm