im in the uk, i have also bought some of that advanced nutrient barricade you suggested. havnt used it yet tho. shud i be using cal mag with all my water? im having trouble with all my plants in rockwool, they just all seem very dull after a few days, and not healthy. im gonna keep things simple for my next lot and only soak my rockwool in 2ml of formulex per litre. i take it i shudnt feed them after that for the first 2 weeks? btw, that barricade is some sort of silicon isnt it? thanks zandor