Click HERE to download as a PDF
In hydroponics, DWC stands for Deep Water Culture, it’s a variation of a standard water culture system. A DWC system works exactly the same as a standard water culture system, the only difference is that the water is deeper than a standard water culture system. Though many people refer to any water culture system as a DWC system, water culture systems aren’t really considered “deep water” unless the water is at least 10-12 inched deep.
Water culture systems are one of the simplest and least expensive types of hydroponic systems to build. Often times you can build a water culture system out of materials you have laying around your house, as we did for this one. This hydroponic system design is really good for growing small to medium size plants nicely. With very few parts it’s not only inexpensive, but very easy and fast to build as well.
- Five gallon bucket with lid
- Aquarium air pump
- Air line for the pump
- Aquarium air stone
- Net Pot
- Growing media (to fill the basket or plant pot with)
- White spray paint (to reflect light/heat)
If your going to be growing small plants you can use more than one basket for multiple plants. That way you can space them evenly apart. We will be growing a medium sized plant, so we will be using one larger basket. You can buy net pots in many shapes and sizes at Greener Side of Life. They look like a spaghetti strainer shaped as a plant pot.
Once you have your plant’s pot ready, you’ll need to cut a hole in the lid of the five gallon bucket to set it in. It’s best to cut a test hole in something first, because if you make it to big, you’ll need a new lid (or bigger plant pot). Draw and cut out your test hole on a piece of cardboard and test by placing the pot in it. If it fits nicely without falling through, use your test hole as the template to draw it out on your lid.
Now go ahead and cut out the hole for the basket in the five gallon bucket lid. The easiest way to do that is using a rotary tool with a drill bit (another very useful tool for building hydroponic systems). If you don’t have a rotary tool you can also cut it out with a jigsaw with a blade for plastic. Just drill a hole large enough to fit the blade near the line you drew (inside the part your cutting out). Stick the blade in the hole and cut along the line. If you have to, you can cut out the hole with a soldering iron as well. It will take longer and make a lot of smoke, but it will work if you need to.
Black surfaces (like your five gallon bucket) absorb heat. It is important to keep the root zone of the plant cool, so painting your bucket white will reflect light/heat -because the actual bucket is black, it will still block light from getting in.
NOTE: A glossy finish is important, it keeps the bucket from getting too dirty to quickly
Now to make it easier for you when you need to lift the lid off (to check pH /water lever, and to feed nutrients etc.) Cut a small notch out of the side of the bucket, near the top to run the air line through just far enough down so it runs 1/2 to 1 inch below (Like the pictures above) the lid . This way it wont pinch the air line, and you can lift the lid easily without dealing with moving or disconnecting the air lines. I just used the soldering iron to burn the notch down the side because it’s easy and gives fairly clean and smooth edges. But you could use a hack saw also.
Some air stones will want to float. You can buy weighted air stones at Greener Side of Life so that you don’t have to waste hours daily trying to weight them yourself. Connect the air lines to the air stone/s, and place them in the bottom of the bucket. Plug in the air pump. Place the lid on the bucket and insert the plant basket/pot. Fill the bucket with good quality water high enough so the bottom of the basket/pot is about 3/4 inch under water. Take the lid back off and mark the water line inside with a permanent marker. Make more than one around the inside so you can see it easily. That way you will always be able to know where the water line is in relation to the basket/pot, even when you have plants growing in them.
With the water line marked so you know how high it is in relation to the plant’s basket/pot, you can easily adjust the water height as needed anytime. So how high should the water level be? There are a lot of variables so there isn’t a one size fits all. There is however a rule of thumb to go by. you want the water to be high enough so the growing media and root ball inside is moist, but not soaking wet. The growing medium should be moist 2-3 inches down (not soaking wet).
Now mix your nutrient solution in the water according to the manufactures directions. Make sure your nutrients are for hydroponically grown plants.
Then check and adjust the pH if needed. Once you have your nutrient solution mixed, your ready to fill the basket/pot with growing media and your seedling or plant. If you started your own seedlings in starter cubes, just fill the basket with growing media and set your seedlings in it. If you are starting with potted plants in potting soil, gently wash off all the soil from the roots. It’s easiest to do that by filling a pail with water and submerging the roots and soil in it. Then gently brush off the soil from the roots by hand while their under water.
Once you have your plant in the DWC system, it will probably take about a week for the roots to start coming out of the plant basket or pot. So you’ll want to make sure your water level is high enough that the root ball gets plenty of moisture. Once the roots hang down into the nutrient solution, the exact water level wont be so important. If the lid of your 5 gallon bucket is hard to get off regularly. You can cut a hole in it to make it easier to add water and check pH. You can just stick a stick in it to check water level, or just fill it until you see water starting to trickle out of the notch for the air line.