The trial with a five-year-old company involved four 20-bucket HydraMax arrays grown indoors without ambient sunlight. The system was monitored throughout the test period for nutrient/water, temperature, oxidation-reduction potential (ORP), electrical conductivity (EC), pH and dissolved oxygen by Nuravine monitoring equipment. Room atmospherics were continually checked for light intensity, dew point, relative humidity and vapor pressure deficit. An Athena Ag Blended nutrient line was chosen for the trial with a standard feeding and irrigation (fertigation) schedule set in place.

With a commercial cannabis operation, variable overhead costs can quickly eat into profits. That’s why savvy growers choose HydraMax recirculating deep water culture (RDWC) systems from Hydra Unlimited. In a recent trial, a 7,000-plant operation saw a significant reduction in water and nutrient consumption when using the HydraMax solution, compared to the grower’s standard coco coir substrate technique. Plus, the investment in expensive, time-consuming water content monitoring was eliminated because the HydraMax buckets are always full.

A typical substrate/fertigation operation utilizes 12 substrate cubes beneath a 1.2 x 1.2m LED light and uses approx. 5,000 liters of water per light. This comes to the 12 plants consuming approx. 50 liters per plant per day for 12 weeks, including plant evapotranspiration and fertigation run-off. A trellised table system running water content thresholding with nine coco coir substrate bags beneath the same lighting will use approx. 1,700 liters of water per light.

With the Hydra Unlimited RDWC trellised table setup, four HydraMax buckets with TetraBase® hydroponic media beneath a 1.2 x 1.2m LED light consume a mere 890 liters of water per light. This typically provides a 50% to 80% improvement in water conservation depending upon the substrate cultivation technique that Hydra Unlimited replaces.

Under the trial’s 30 m2 lighted canopy, the 80 plants utilized 2.6 liters of water per plant per day and consumed a total of approx. 17800 liters over the 12-week grow period. This represents a 76% reduction in water consumption over the operation’s standard substrate methodology and generated a total cultivation cost (nutrients and water) of €13.10 per plant.

“We were pleased by the results of the trial,” said Hank Bonnah, Hydra Unlimited principal engineer and chief scientist. “Less water used meant reduced nutrient waste. By targeting the crop’s fertigation consumption, the HydraMax solution dramatically dropped the per-light cost of cultivation.”

Made in the USA, Hydra Unlimited’s HydraMax is a complete commercial deep water culture system. With best-in-class aeration, nutrients are quickly and evenly delivered to each bucket simultaneously. This results in consistently faster vegging, higher yields and greater profits.