Undecided about how to grow your cannabis? Looking for a change? Have you considered a bubbler deep water culture (DWC for short) system? The principle with bubblers is simple: the plant is suspended above an oxygen-rich nutrient solution. The roots of the plant hang down into this solution which feeds them 24 hours a day, allowing for super-charged growth and development of both plant and produce. Bubblers are versatile in letting a person grow a single plant, where space is limited, or they can grow many plants. There is no soil or coco medium to worry about with bubblers, meaning less mess and hassle. Most important, a DWC system has the potential to yield massive results with little input. Isn’t that what everyone is after?
Considerations Before Adding Cannabis Plants to a Bubbler
So where do you start? Well, bubbler kits are sold as single units (pots) that hold one plant. Brands differ in style but generally, they all do the same thing. However, as the system will be filled with water, the last thing you want is a leak, so a good hack to check for leaks is to fill your system up in the bathtub and leave it for several hours. Like any product, it is possible there could be some small manufacturing fault that could cause a leak, so it is best to eliminate this risk before you use it.
How to Transplant Clones/Cuttings to Bubblers
Once you are satisfied everything is watertight and in good working order, you should transplant your cutting/clone. Your plants should be ready to go into the vegetative stage and be able to handle a strong intense light and feed increase. Cuttings should have three stages of nodes which are the vertical levels on the main stem where new canopies of leaf formations grow from. If growing from seed you are likewise looking for them to have either three stages of nodes or to have rooted through a three-inch block of stonewool, both of which happen at around the same time.
When transplanting, I usually add about half the clay pebbles, place the stonewool cube in, and fill up with more clay pebbles until it is level with the top of the stonewool cube. This way you are not pushing or forcing the stonewool into the pebbles and you will cause less damage to the roots.
Tips for Setting up Your Bubbler
Growing in a bubbler follows the same timetable as growing using most other systems: four weeks in vegetation and eight weeks in flower. Some good tips to remember when setting up your bubbler include the following:
Keep your electric pump motor away from the water in your bubbler. I'm sure you don’t need me to tell you that water and electricity do not mix.
For best results make sure the air being pumped into the water is originating from an external source so that it is the freshest that it can be.
The positioning of your air stone is crucial. Make sure it is centered in the bottom of the main reservoir, so all the plant’s roots are receiving an optimum and fair distribution of oxygen.
To start, your plant’s roots will not be long enough to reach the nutrient feed in the water, so it is best to overfill the bubbler so the water reaches half way up the net pot and the roots can drink with ease.
Use a temperature monitor and control to keep your nutrient solution at optimum temperature between 64-68°F. The warmer your solution is, the lower the oxygen level is and the lower the nutrient uptake is. Keeping the solution at the perfect temperature will also help keep algae and diseases (that thrive at higher temperatures) at bay.
Make sure your nutrients are suitable for a bubbler or, even better, are specifically designed for bubblers. You want to avoid products containing organic ingredients like seaweed and molasses, which when oxygenated, can foam and ferment, forming sticky residues that can block pumps, destroy air stones, and lower oxygen levels. Bad news all round.
Now that you are all set up, how do you keep everything running smoothly? The first thing to address is how often should you be topping up the solution in your system. The answer is whenever your plants need it. The golden rule is 90 per cent of the roots should be constantly submerged. You should prioritize this in the first few weeks, as the plants are establishing and strengthening themselves.
Managing Electrical Conductivity Levels in Bubblers
Electrical Conductivity (EC) and pH management are crucial in telling you if your feed strength is adequate for your plants. If the EC suddenly shoots up, resolve the problem by adding fresh water until levels are back within range. I would check them once or twice a day to keep conditions perfect. You can find the EC and pH goal for bubbler systems week by week on any good feed chart. If EC levels drop below range, I would replace all the liquid in that pot with a fresh batch. This is because EC only gives an indication of the level of chemicals in the water. If the EC drops, then all we know is the plants are taking up more nutrients than water. We do not know which element a plant is taking more of though, and so removing all the liquid ensures we are not overfeeding the plant with any one element. Bubbler EC levels, however, are prone to fluctuation, so if you do see a change, give it an hour or so and check again before taking any action, as it could well return to normal levels within that time.
Replacing the solution in your bubbler becomes more challenging as the plant gets bigger and heavier. It’s best to prepare in advance for this situation. Prepare a new reservoir with fresh feed solution, then gently but firmly lift the plant out of the bubbler by the main stem supporting the root mass with your other hand (the lid and net should still be attached in the middle) and then quickly place the plant into the new pot. You can then clean out the old reservoir and repeat the process with all your other bubblers. You should perform this process quickly and efficiently as to cause a minimal amount of stress to your plants and to limit the roots exposure to the light. Speaking of roots, be sure to check, as time goes by, that the roots are not growing entirely around the air stone. If this happens, gently remove the roots as they can affect the rate of oxygen distribution in the reservoir.
It’s no surprise that bubblers are one of the most popular systems on the market today — when everything is going well, they are one of the easiest systems to assemble. When used with care, the bubbler system can be your best friend giving you bigger, faster-growing plants at a low cost.