mobay have u tried coconut fibre as ur medium , i use it with clay pebbles but u could use perlite as well, the + points about coco fibre is that its has a neutral ph to start with , plus it is light and airy allowing alot of oxygen to get to the roots . i, as u well know have just set up a new grow set up , and i was going to get myself a hydro system but after reading the pro's and cons and seeing the result i was getting from the coco fibre i opted to ditch the hydro plans and just use the hydro feeds instead and feed them every time i watered . and it seems to be workin a treat .
SH
ps. my mate has grown ice in the past , great high but not the best yeilder. Ice is used in holland to make the hash called iceolater.... very trippy high.:rasta: