In an attempt to make amends for totally jacking Tylergvolk's (sorry and thank you) thread here I would like to post on the OP's original question of wether to dose the water column or not. I am no expert, a beginner really, but I have read a lot of stuff and know the theory at least, so here's the consensus. While some, especially nature types, may still advocate soil only nutrients few would say to give nothing at all to the water for the leaf intake, and most agree with the high production folks approach: dose the soil and the water column. The logic is sound. Dosing properly does not promote algae it prevents it, so dosing the water adds redundant backup. But, you say, why would my soil fert not work? The chemistry of plant nutrition is complex, dynamic and unique to each tank. Factors may exist in your tank which may block the availability to your plants of certain present elements. No one knows everything that's going on in the planted tank and redundancy is insurance. On the other hand, If you have time and experience and observe the reactions in your tank you certainly can produce fantastic results without redundancy.