Cloning with Aeroponics for DWC

A friend of mine that grows for a craft cannabis producer sent me a photo of the aeroponics cloner they use for commercial production. 10 days from cutting he had MASSIVE healthy roots with no rockwool. I had to recreate this at home.

Aeroponics is the process of growing plants in a mist environment. Often cited as the most efficient method of nutrient uptake by NASA experiments that researched growing high protein beans in space. Aeroponics is new to me as DWC has worked so well I have not had to look into atomizing the nutrient solution. If roots can sit in the nutrient solution 24/7 why bother with water pumps and misting nozzles. For mature plants I still believe aeroponics is not necessary. DWC is so much easier.

For clones and seedlings – aeroponics makes sense. I tried cloning in DWC with limited success. The cuttings would get waterlogged and rot away before the roots had a chance to develop.

Low-Pressure VS High-Pressure Aeroponics

Aeroponics can be divided into two categories.

Low Pressure Aeroponics – is usually done with a submersible pump. The water/nutrient solution is sprayed rather than being atomized into a fine mist. You can use a regular garden sprinkler/sprayer or misting nozzles as pictured below.

this would be considered “low pressure” aeroponics

High Pressure Aeroponics – uses 60+ PSI and misting nozzles to create a fine, atomized mist of water/nutrient solution. High-pressure Aeroponics requires a diaphragm pump and accumulator tank to generate the necessary pressure.

This guide focuses on Low-Pressure Aeroponics because it works fine for cloning/propagation and is a much easier & cheaper build.

This method of cloning falls directly in line with my low maintenance philosophy. No need to mist a humidity dome. The foam cuffs are re-useable. There is no rockwool that serves as a home for algae and other pathogens.

The Build

Part List for the Build:

Drill Holes for Foam Collars

If you drill 1 3/4″ holes it will be a perfect tight fit for 2″ collars. Avoid using net cups in the cloner unless you want to deal with untangling the roots out of them later.

Foam Vs Neoprene Collars

If you look for 2″ foam cuffs on amazon you can choose between neoprene and foam. My local hydro store only had neoprene so I ordered some foam online to compare. The foam cuff is much better. It holds no moisture, unlike the neoprene which felt soggy and soft after a few days.

Wire/Airline Routing

The foam collars work well to route the cable out of your bucket. I used to run the cable out of the lid but that made it impossible to remove the lid fully without unplugging the pump. Drill a 1/4″ hole for standard airline tubing.

Pump Timing Cycles

Cloning : 1 minute on, 20 minutes off

: 1 minute on, 20 minutes off Germination: 1 minute on, 60 minutes off

Cloning Temperatures and Humidity

Water Temp: 68-80F (I prefer 68-72F)

Air Temp: 55-80F (ideal range is 70F)

Humidity: 35% – 80% (Yes I have cloned down to 35% humidity with this method!)

Running the sub-pump on a timer also helps lower water temperatures. Any more than this and I find the sub-pump increases my water temperatures beyond what I consider an acceptable range. People on Reddit have mentioned they like to go up to 80F for cloning but that exponentially increases your risk of infection. I like to keep water temps under 72F.

Modifying the Pump: Misting Nozzles / Sprayer & Filter

Drill appropriately sized holes for the misting nozzles. The drill size for my nozzles was 1/8″.

I use a tea strainer hot glued to my sub-pump to prevent small bits of roots from getting inside the pump and impeding the motor. Learn from my mistakes, this is necessary and your pump will clog without it. The tea strainer is easy to clean and can be found online for $10.

tea strainer used as filter for sub pump

You could likely save a few bucks by using a sprinkler head rigged up to the sub pump with a small 6″ riser. I went with PVC since I already had some around from my SCROG build.

Don’t forget to put an airstone in your bucket. Although you may think the water is being aerated by the sub-pump, it is not. The system needs fresh oxygen from outside the bucket.

Lightproof Air Exhaust.

The air pump will create positive pressure in the bucket which can create water leaks when the sub-pump kicks on. In a typical DWC reservoir, the hydroton will allow air to escape, so these exhausts are not necessary.





To create an air exhaust drill a hole in the bucket lid and cover it with a flap of double-sided duct tape to prevent light leaks.

Sterilization

Sterilizing the pump, container and foam pucks is very important. Cloning creates an open wound on the plant, making it susceptible to infection. Luckily sterilization is very easy since the pump does all the work for you. Fill the bucket with 1 gallon of Star San solution (6mL of Star San/Gallon) and run the pump for 5 minutes.

Star San is a food-safe non-rinse sanitizer that is commonly used in homebrewing. You don’t need to rinse the remaining foam after sterilization. This is because it is an acid-based sanitizer, so any remaining foam is rendered inert when diluted by water. Dump out as much sanitizer as possible and proceed to the next step.

Aeroponics Cloning Nutrient Solution 1 Gallon Water

pH down (Target pH 5.5)

FloraMicro 3 Part Series (1 mL each Micro, Gro & Bloom)

1.2 mL of Rapid Start A few drops of pH Down gets me down to 5.5 Unlike soil (which has trace nutrients) cloning/germination in hydroponics requires immediate additions of nutrients. Once you get the pH to 5.5 add: 1.2 mL GH Rapid Start

1 mL of FloraGro

1 mL of FloraMicro

1 mL of FloraBloom My starting ppm was 100 and the final ppm was around 300.



The result

6 days after cutting roots are starting to show

12 days after cutting

This is what we’re going for. Healthy white roots ready to be thrown into a 3″ or 6″ net pot with hydroton.

Aeroponics Seed Germination

Seeds can also be germinated using these cloning buckets. Check out my guide on using rockwool sleeves to germinate for DWC.

Black Bucket Vs Painted Bucket

If you can find a black bucket I strongly recommend it. Or at the very least get a black lid. Spray paint likes to chip off the plastic and will find its way into your water. Give your local aquarium supply store a call and see if the have any extra coral salt buckets.

Totes VS Buckets for DWC Cloning

flooding created by sub-pump used with tote

As I was getting ready for work one morning I checked on the ladies to find my plywood grow box was flooded. The pump had slowly sprayed a substantial amount of water out of the tote I was so used to using for DWC. While drying out my grow box I decided to switch over to a 2.5 gallon bucket with a rubber gasket lid.

This was also before I had installed a pressure release valve so it is likely that my air pump was forcing water out of my tote through the sides.

My Experience using Rockwool with DWC

Rockwool and humidity domes have always been synonymous with cloning plants. Although I have had success with using rockwool, there are a number of problems with it in DWC grows. Rockwool holds water, which can become stale and unoxygenated. Traditional humidity domes run at 100% humidity which is an invitation for mold and bacteria to develop. This mold/bacteria can spread quickly in DWC systems.

Clones that got waterlogged and died in rockwool

Sidebar: Do Not use an ultrasonic fogger for cloning

My first attempt at aeroponics involved the use of a $17 ultrasonic fogger. These are often used in cool mist humidifiers or reptile foggers. An oscillating ceramic plate atomizes water into particles that are 3-5 microns in size.

cuttings that were suffocated by a fogger

The cuttings were killed by the fogger in a matter of 24 hours. Because the mist is so fine it blankets the cuttings, not allowing air to get to them. I had the fogger on a cycle timer running for 3 minutes on and 15 minutes off. I could have tried to introduce air into the box but this would be too much hassle. In addition, I have read that people were having problems with the oscillating plate clogging up and having difficulty atomizing nutrient solutions which have ions 40-50 microns in size. For $17 it was a worthy experiment, but this fogger ended up going back to amazon.

I did have a reddit user message me saying that he uses ultrasonic foggers without issue for cloning. His setup seemed similar to mine. If you have any experience using foggers shoot me a message on reddit.