it would be significantly less nutes goin to the plant cus its the right amount for h2o and reg nutes have higher concentrations of nitrogen and other elements simply due to the fact that the soil will hold 3/4 the nutes in the soil,and when you give them pure water it flushes out the other nutes,making it less concetrated over time,then u refertilize.you would have to use so much hydro nutes in the soil that it would cost u more than an arm and a leg to make any differance and thats for one feeding.