Equipment
I use a system called Deep Water Culture (DWC) growing the plants in black buckets using an air pump to circulate the water. During the vegetation stage, about 6 weeks, the light will be on 18 hours a day and 12 – 20 inches above the tops of the plants. I fill the buckets using the schedule on the Nutrients page.
To prevent problems with disease and bacteria these buckets need to be sanitized regularly and as light tight as possible.
Finding a black bucket that actually blocks the light was difficult. A cheap set of hole saws cut the various holes needed for vents, taps and the pump cords for the Aeroponic bucket. I have found a better, water tight fitting for the vents [NPT 1″ Cord Grip Cable Glands, Waterproof Adjustable 18-25mm Plastic Cable Connectors Nylon Joints with Lock Nut and Gaskets] and replaced the bubblers with a 5 inch air stone. I have two air pumps running with 3 buckets attached to each one providing a very powerful air flow to move the roots and keep the bucket well aerated. This way I always have a back up air pump ready to go in case one dies.
Deep Water Culture Bucket 
Basic DWC setup 
All parts for DWC bucket 
The inner mechanism of the tap is made of a translucent plastic that readily transmits light. 
Flexible silicon caps (5/16 inch) slip on to block the light. 
5 inch pawfly air stone 
Air vent parts 
Air vent is tilted up to keep any condensation from dripping on the floor. 
Inside bucket 
Air stone in action 
Excess trim is removed after cutting hole for net pot 
Bucket is sanitized before use. 
Checking pH. 
Net pot with plant is placed in the lid. A strip of aluminum foil is used to block light and two small sand bags hold down the foil and help stabilize the plant. 
Excellent root growth
The taps come with clear gaskets. I used heavy O-rings as gaskets for the tap and air vent because I could not find any flat, black ones with 3/4″ and 7/8″ ID. I used O-rings on both sides of the bucket as added insurance. If you don’t overtighten them they work.
I use grow rocks as a medium to hold the plants in three inch net pots. They are made from recycled glass, very porous and light weight. It is reusable, unlike the clay pellets commonly used in many cannabis hydroponic setups. This is a great product that is no longer being manufactured as the company seems to have gone out of business, although it may still be available online.
In tent A I use a Mars Hydro TS 1000w LED light and a Spider Farmer SF1000 and in tent B I have a Spider Farmer SF2000. They provide the intense, well balanced light needed to maximize plant growth and flower production. In tent A I set both lights to 300 and in tent B 600 watts (rated) when new clones are moved to the buckets. I slowly raise the the light level to 1000/2000 watts (rated) by the beginning of the fifth week . While the plant is developing I rotate the plant so the smallest stem gets the most light. This along with using wires to bend the stems helps shaping the plant to keep all of the tips about the same height.
Two 1000 watt (rated) LED in tent A 
To prevent burning the leaves the Mars light needs to be farther away from the plants.. The hood focuses the light on a smaller area. 
2000 watt (rated) Spider Farmer LED in tent B. Excellent coverage at 2 1/2 sq. foot. Greater density of LED diodes around the edge evenly distribute the light. 
The control for the dimmer on these lights is on top and cannot be removed. I had to extend the cord to reach the regulator.
The plants
Depending on the number of buckets I will have in the tent I start with either four or six main stems, I try to start these stems as low as possible and keep them level with each other.
Four stems are easy to manage and this allows plenty of room for light and air to get to the lower colas.
Starting with 6 stems will give you an extra if one breaks while training or moving them around. You can remove the two weakest stems in the first month to end up with the 4 sturdiest stems.
When starting with 6 stems when you only need four remove the smallest stem after two weeks in the veg stage . At the end of three weeks remove the smallest stem leaving the four sturdiest stems.
Once the new clone/seedling is placed in a bucket it is important to keep all of the stems below the shortest / thinnest stem. The plant will always send more nutrients and resources to the tallest stem. This will help the stem grow quicker and thicker. This will be an essential part of shaping the plant to prepare it for the flower stage.
It is very important to check each plant daily to make sure that new shoots are forming. This is a key indicator of the health of the plant. If the plant is stressed the growth will slow. Each strain will grow at different rates so it helps to learn their normal growth pattern and watch for any change.
Keeping the stems about equal in height and thickness is my goal when shaping plants during the vegetation stage. As the plant grows some stems will grow faster and I will need to raise the lowest/thinnest stem up above the rest. The plant will then send more resources to this new top stem. I achieve this by attaching a wire below the 3rd or 4th node of the lower stem, pulling it up above the other stems.
I keep 4 to 6 large fan leaves on each stem, removing the oldest leaves as new ones form. I end up with a skirt of large fan leaves around the outside edge of the plant. The stem tips will be under the most intense light and the outer leaves fill the area to the tent walls. This allows good airflow around the base of the plant and removes the less efficient older leaves which are mostly shaded anyway.
Each day I need to make sure the growing tips on all of the plants are not covered by new growth from the fan leaves. These large leaves will push upwards towards the light. Sometimes I can weave the leaves under other stems but if I can’t I will remove these top fan leaves.
I begin letting side stems start to grow a week before the flower cycle starts. The flowers will form on these stems and this insures there will be enough to form a solid carpet of colas under the lights. I will begin removing a couple of the largest and oldest fan leaves daily. By the 3rd week flowering I want to end up with two large leaves on each of the 4 main stems.
Growing medical cannabis 