Ah Razz, NPK is something that you need to know to build up your basic foundation. N* Nitrogen, P* Potassium K* Phosphorous . These are the major macro nutrient make ups in all fertilizers. In veg you need a nute with a high N and in flower you will want a nute that is high in P and K. You will find this on all fert bags and bottles. I am giving you a basic description, but you want to take about a half hour and do some reading on the MJ plants need for NPK and how it plays a major role in having a good grow, as a matter of fact here is a link for you, www.marijuanagrowing.com/article.php?sid=26 .
Get the moisture tester and you will save your self allot of guess work on the watering thingy IMO. DWC is "Deep Water Culture.
" I have a thread in the hydro section titled "Water Farm/DWC club where you can pick up some idea on what it is as people dialog back and forth, but in short it can be set up using a 5 gallon bucket with a net pot in the lid of the bucket that holds grow rocks and your plant. You fill the bucket with your water/nutes and get a $10 air pump from Wally Mart and get these little $1.50 air stones that they use in aquariums and place two in the bottom of the bucket and the water is saturated with O2 as the air stones produce bubbles in the water and splash onto the roots of your plant feeding it and watering it. The plant is able to experience amazing growth because un like in soil where the plants roots have to stretch out threw the soil to find food and water, the nute/water is given directly to the roots every second and the plant is able to focus its energy on growing buds instead of roots. When done right, up to 3 ounces can be harvested from one plant with a veg time no longer than 3 weeks and in soil this is a really hard thing to do..
Adieu