Maintaining proper water levels in RDWC or your Under Current system is an essential part of successful plant production. Though often over looked, improper or sudden changes to water levels can cause undue stress which could negatively affect yield and quality. We’ve designed our Under Current RDWC system to allow the grower total control of all system functions, such as water levels at all times.
Importance of Maintaining Proper Water Levels
Unlike other forms of cultivation, RDWC is unique in that highly aerated water replaces soil as the grow medium. Because water takes the place of soil, any water level changes can induce stress. Fluctuations in the medium can result in stalled growth or cause a plant to not reach its full potential.
Low water levels can prevent roots from reaching the water, which will result in severe plant dehydration. Symptoms of dehydration include wilting, dull leaf texture and signs of nutrient deficiencies.
Water levels that are too high can have equally negative impacts on plant growth. High water levels will cause over saturation of the root crown which can stunt growth or cause damping off. Signs of high water levels are root disease, leaf yellowing and vegetative die off.
Water Levels In the RDWC Under Current System
Any water level adjustments must be done slowly to prevent any undue stress. Usually this is done incrementally early in the plants life cycle as roots stretch from the root crown through the net pot chasing their medium.
Early Growth Stage Water Level
- Water levels should be maintained at 1/4“under the top of the 2” inch planting deck when using Rockwool, or under the root crown with a bare root cutting.
- This water level should be maintained until there is sufficient lateral root growth through the net pot.
- Be advised when using rock wool or similar media, to set water levels just below the bottom of the Rockwool cube to prevent over saturation.
Late Growth Stage Water Level
- Once there is sufficient lateral root growth through the net pot, set water levels 1/4” under the bottom of the 8″ net pot. Approximately week 2 of veg.
- This is where water levels should be maintained the remainder of the plants life cycle.
Maintaining correct water levels during the vegetative phase will encourage dense lateral root growth. This root growth establishes a foundation for increased yields during the bloom phase of growth.
Water Level Adjustment
In your Under Current system adjustments to the water level can be made by adjusting the Epicenter Float Valve upward or downward. Start by loosening the Float Valve thumb screw, then adjusting the Float Value up or down until the desired water level is achieved, and finally re-tighten the float valve thumb screw. It’s as simple as that. It is strongly advised that a gravity fed top-off reservoir is used with your system. By using a top-off reservoir you can easily maintain accurate water levels throughout the growth cycle in your Under Current system.
- Note: Level surfaces are needed in order to maintain even water levels. Uneven flooring can cause inconsistent water levels which can cause problems.
Tips and Tricks
Water level adjustments late in the bloom cycle will induce a stress response that mimics drought conditions. This induced stress will cause the plant to increase its essential oil production late in bloom. Note this technique should only be done on a healthy plant. Starting incrementally in week 5 of bloom reduce water levels approximately ½” per week in an 8-gallon, or 1” per week in a 13-gallon module until the end of the growth cycle.