is there directions?? I have apart 1 and 2 solution that I feed my plants but it is not sensi.....prob the same principle though so I will tell you how I do it... I use a 9 litre bucket and put some water in then add the part A using a massive syringe to draw it out,,the amount you need to use is in your directions..usually a amount of mls per litre ..the syringe has the mls clearly marked on the side so its easy to get the right dose....its way better to under feed then over feed,,so I always use a little less then the recommended amount ...then I add the part 2 after mixing in more water and rinsing the syringe out.. my part 1 and 2 are used in exactly equal amounts ....then I top up the bucket and pour it in the res..... hope this helps..... :^)