In addition to dissolved nutrients, cannabis roots need oxygen to continue serving their function in the plant. Air stones inject bubbles into a hydroponic nutrient solution, but the sound of buzzing air pumps is hard to get used to. Check out this simple solution that aerates your water with no noise, and a lesser cost than air stones and pumps.
Cannabis plants that grow in soilless mediums become highly sensitive to the quality of the water around them. When growing directly the water without any of the natural buffers that soil provides, slight changes in the conditions will impede growth the moment they take place.
In addition to pH, nutrient concentration, total dissolved solids, chlorine and temperature, dissolved oxygen is another key factor to consider about your nutrient solution in order to maintain the health of your cannabis plants, and in particular their roots. Cells in plant roots, which do not receive any light, burn simple sugars to stay alive and do what they need to do, a process that requires a constant input of oxygen.
Most growers use noisy air pumps that push air into chunks of porous, volcanic rocks called air stones, which provide adequate levels of dissolved oxygen in the area around them. Depending on their setup, a hydroponic cannabis grower may put airstones around several locations of their setup to prevent any part of their nutrient solution from becoming stagnant, or void of oxygen.
The poor efficiency that air stones provide for aeration means even small scale growers always need several air stones and maybe even several air pumps. All these parts add extra expenses to the setup cost, a lot of extra noise generated in the finished growroom or grow box, and a lot of extra work required to clean the air stones every time they get clogged.
Using the Venturi Effect, discovered by an Italian physicist from the early 19th Century, a grower can pump water from one place to another and aerate it at the same time using about $15 worth of tubing parts. Using a special arrangement of tubing, the Venturi Effect uses the energy from you water pump to inject air into the stream of water. By aerating and pumping your water at the same time, grow setups can be radically optimized to eliminate pesky air stones and noisy air pumps.
So what is it exactly and how does it work? Basically, the finished Venturi “pump,” when used for hydroponics, is a small section of the water tube coming from a water pump and onto a reservoir. This section consists of adapters that make the tube of water temporarily thinner, and then back to the original diameter. At the spot where the tube is thin, a smaller tube is connected perpendicularly. It may seem counterintuitive, but when water passes through this thin segment of tubing, its pressure is lower than at the wider points. As water under pressure is forced through the tubing, the sudden drop in pressure sucks in air through the tube that is attached perpendicularly. This creates an intense vortex of bubbles that instantly oxygenates the nutrient solution for your plants.
You can build a Venturi “pump” yourself using easily obtainable parts from a hardware or aquarium store without raising any suspicion. Check out this video for an in depth explanation about different way to make a Venturi water aerator. Happy growing!
Photo Credit: VortexFarmacy