All good stuff mate thanks makes complete sense, Ill run both of these water test's nice one, Ive since been thinking on the filter problems associated with using soil & a dripper recirculating system, do you think that placing some sort of fine filter at the point the run off enters back into the tank? Ive also seen some filters which actually connect to the irrigation system but since they look far too small to be of any use & dont have a clue how they work exactly I think Ill give them a miss. As for the two sections is having a Clone/Mother section, and place strongest clones to Veg & Flower section not more useful than having an exclusive flowering section & an separate Veg/Mother/Clone room. Which ever is best I will go with. Its mainly because I want to just use CFL's in one room and save my 400w + 600W for strong Veg & Flowering Cycles.