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The Benefits of Running a 20 Plant per Light Setup in a Closed Loop Aquaponic System

I’d like to demonstrate how farmers can sustainably optimize annual crop production values on a gram/meter basis by reducing harvest times in a closed loop flood and drain aquaponic system that utilize LED Grow Lights with UV attachments in 4 gal plastic pots (20 plants/light) with plants that veg for only 5 days from rooted clones.

The plants are flowering in our 40’ tractor trailer which is elevated on one end to allow us to flood and drain the pots with our recirculating aquaponic fish water. As the table is flooded with fish water, the water seeps into the holes on the bottom of the pots which pushes oxygen into the root zone. Once a week trace minerals that are not available in the bottom fed fish water are added to the flowering plants through a top water feed coming from a separate dosing tank. Your plants are getting the benefits of both aquaponics and hydroponics from a closed loop feeding that utilizes only 5% of the water usage when compared to top fed soil gardens.

The secret to making this all work is that each plant is it’s own little ecosystem. There is a 4" layer of lava rock at the bottom of the pots which really plays an important part in the overall aquaponic systems balance. Since the lava rock is porous it allows beneficial bacteria to live within the lava rock. The beneficial bacteria consumes the nitrites from the fish waste and expels nitrates which of course are the macronutrients necessary for happy, healthy organically grown plants. The plants need the fish and the fish need the plants. Symbioses baby!

Above the lava rock we use a spun rock media by Growpito that is unlike any media we’ve ever used. If you’ve used Grodan Cubes you already know how well plants perform in this type of media. The water and nutrients stay in the root zone for much longer periods of time meaning your watering schedules and nutrient doses are dramatically reduced. The major difference with Growpito is that unlike Grodan cubes Growpito is not a solid cube but instead is a highly fibrous fluffy material that goes into your pots much like a coco coir planting. This is important since the way we’re using this media requires a bottom feed with our aquaponic water. With Growpito the water entering and rising inside the pots not only acts to keep the beneficial bacterial alive inside the lava rock but it also acts as a diaphragm pushing any oxygen that is trapped in the pot up into the root zone every time we flood and drain the table. Growpito is not compressed like a Grodan cube so air is able to circulate throughout the root zone far more efficiently and happy roots do make happy fruits!

The other major benefit of Growpito over Grodan is that Growpito is sustainable meaning it only needs to be bought one time and will be used over and over again. With Growdan Cubes you end up either throwing the cubes out or take them in for reprocessing. That is not the case with Growpito, We know of gardens that have been using the same Growpito for 10 years and 40 harvests. When maintained, Growpito actually gets better with age. Imagine not having to buy media or having to drive down the hill to get more media ever again! That’s what we’re talking about here folks. Your farms help lower your overall carbon footprint with a product that is not only better for the environment but better for your plants.

It’s also important to note here that since the laws for growing cannabis are increasingly focused on the environmental impacts of our cultivation practices. If your cultivation methods divert excessive amounts of water or generate excess waste runoff from your property, you are very likely going to be shut down by an environmental agency regardless of whether or not you are a licensed Cannabis grower or not. This is another reason what we’re describing in this album relies on the farm requiring less water to begin with and zero water runoff by maintaining a closed loop system. When using this combination of Aquaponics and Growpito media you are utilizing sustainable cultivation methods that will not run afoul of those environmental agencies who would oversee any and all licensed or unlicensed cannabis cultivation activities. For example, in California you can see how our recently passed ‘recreational’ cannabis law, Prop 64 AUMA, specifically addresses water diversion and waste water discharge issues which by law gives various state environmental agencies the authority to revoke a cultivation license as described in SECTION 2- FINDINGS and DECLARATIONS paragraph (F):…/i…/pdfs/15-0103%20(Marijuana)_1.pdf

So what can we as growers do to mitigate these issues so these agencies don’t come down on us as being a ‘bad actor’ and put us out of business? We need to be smart and we need to have a plan that puts us, the cultivators, at the leading edge of energy and water savings strategies while still making a profit and providing the market with the quality organically grown plant products that are increasingly becoming the sought after standard for our industry anyway. When it comes to water conservation the only times you’re adding water in these closed loop systems is to replace water losses from evaporation or plant uptake. When it comes to the nutrients, fungicides, pesticides, and aerocides with aquaponics you can not put anything on the plants that would harm the fish. So when one of these agencies comes in to inspect your facility you’ll be able to show them happy fish and amazing plants that derive the majority of their nutrients from fish waste. The fish really are your ‘canary in the coal mine’. To learn more go to;

In this album we show images of our 40’ flowering trailer that shows 4 each x 23 rows = 92 plants in 4 gallon pots under our Impact Series Grow Lights. The entire trailer bed is a flood and drain bed with the fish tank located just beneath the trailer. These plants will acclimate in the trailer on an 18/6 lighting schedule with the Impact Series lights set on the High Veg setting for 5 days. At day 6 we will put them into a 12/12 schedule and add the reds on the Impact light so the plants will be getting a broad spectrum while in their flowering state. We also will be running our UV-Pontoon which is an attachment to the Impact LED lights which as you will see by adding these UV spectrums we are giving the plants positive stresses which increases plant and flower size for increased levels of THC all while suppressing mold and mildew. Say goodbye to powdery mildew! For our current trials we are controlling the UV spectrums at 1 hour on and 1 hour off integrals throughout the lights on photoperiod. To learn more about the UV-Pontoon go to;

The area coverage for the Impact Series LED Grow Light is 20 sq-ft which allows us to put 20 plants under each light. Keep in mind that these are not ideal environmental conditions as this is an uninsulated tractor trailer, we conduct tours of the farm and we are not using supplemental CO2 each of these plants yet we will still yield between 2-3 ounces per plant. On the low end this yields 40 oz (1120 grams or 2.5 lbs) under a single 740 watt light with the UV-Pontoon adding another 80 watts puts us at 820 watts at the wall. Again this is on the low end. The average weight we pull is closer to 3 oz per plant, or 60 oz (1680 grams) per light. Thus factoring the total wattage per light @ 820 watts this would put the yields between 1.4 - 2.4 grams/watt or 56 - 84 grams/sq-ft.

When considering the uMol/watt lighting efficiencies coupled with the lower temperatures, not having to relamp your lights, decreased times to harvest (6 crops per year), crop quality improvements from broad spectrum lighting, as well as the controls that allow the utilities to incentivize the use of these lights (programs such as Automated Demand Response to lower your rates) there is not another technology or controls that will deliver an ROI like the Impact Series LED Grow Light. Learn more about the programmable controls features @

In commercial cannabis cultivation those who will have the greatest successes will be those who take take a long vision approach to the industry. In a regulated system profits will only come to those farms that consistently produce top quality products at reduced costs. The Impact Series LED Grow Lights are the right tool to help you accomplish that job. There is a good video that describes the various features of our lights and controls as well as the product specs and utility incentive links @

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If anyone reading this would like to visit us at 151 Farms and see these gardens in action we welcome the opportunity to meet and show interested parties how this symphony of fish and plants comes together so elegantly. To learn more visit us @

Thank you for your consideration.