Aero/DWC Unit

Discussion in 'Advanced Growing Techniques' started by GrapeStreet, May 8, 2011.

  1. #1 GrapeStreet, May 8, 2011
    Last edited by a moderator: May 8, 2011

    Here's the idea.

    So we've got a 28G container, this model shows the possible mobility added by the dolly, allowing for individual bays to be moved between central reservoir arrays.

    You can see there's 2 feeds and 1 drain for both the hydro and aero portions of the unit. This allows for an even flow throughout the roots, instead of the straight-through method of the Undercurrent. This also ensures there's no thermal gradient within the unit. Cooler water from the central reservoir will flow downward, taking any heat with it through the drain and back to the main reservoir, and maintaining an equal temperature throughout the bays.

    The delivery pipes are cut to become channels that overflow upwards, preventing damage to the roots by excess force of water, and also acting as an anti-siphon, preventing backflow should the pump fail.This also ensures constant agitation of the surface, preventing buildup of biotics and hard surface tension that lowers oxygen dissolution rates and promotes mold growth. In fact, this method actually increases O2 levels without a bubbler by cascading the water instead of pumping it in from the bottom.

    At the bottom is a framed "noseeum" screen (20 mesh) to prevent roots/debris from exiting and potentially cloggin the drainage. By providing maximum drainage surface, we can also ensure that flow remains constant through the entire tank, and prevents a vortex effect that can damage roots and cause buildup.

    The drain pipe is an inversion of the two feed pipes, cut with a channel down it. This manner allows for an equal negative pressure from front to back, and on both sides of the reservoir. Again, this is to create an "even flow" scenario and prevent pocket vortexes.

    The aeroponics system is a 1/3 scale mirror of the hydroponics system, set a couple inches above the water line.

    Instead of installing nozzles into each unit, the same method is used as for the hydro section, with pipes cut in half longitudinally, and vapor, created by ultrasonic fogger in the central res, being forced by positive pressure through the pipes and into the upper cavity of each bay. This prevents blockage of the system, and increases kinetic efficiency, requiring less power to run the fogger and fan than a high pressured pump required for fine vaporization.

    You can see the basics of the piping here. There's 4 main lines. two 1" lines run the aeroponics system. The lower line connects to a venturi inlet on the far side of the return pump, inside the central reservoir. The pressure of the water flow will wick air through the aero system, creating a constant negative pressure on the drains and circulating the ultrasonic fog produced in the upper portion of the central res.

    So my implementation is the aero/hydro combo. If the upper portion has the ability to super-branch, and create micro roots (as we have seen with mist-type aeroponics), the branching and growth on top should be increased, while having a solid deep water culture below it ensures there's no lack of moisture if anything should go wrong, and also provides a larger thermal and nutrient bank.

    the 2" floor line goes to the return pump, the 3" line is fed from an overflow set at the desired height, within the central reservoir. As the central reservoir fills from the pump, the overflow is allowed to equalize with all the tanks.

    Should the power or pump fail, the system will not drain or dry out. If both the air pump and the water pump go out, you've probably got between (guessing) 8hr and 48hr to correct the problem before the system is O2 deprived, but for that amount of time, every reservoir has the same amount of water in it, and should a thermal gradient exist (even a small one), then a micro circulation will occur.

    If the fogger or fan goes out, the system will continue as a DWC and the humidity from the cascade should maintain the aeroponic root structure. If the DWC return pump fails, being a negative-pressure system, all reservoirs will remain at optimum levels until power is restored and the fogger will maintain oxygen dissolution levels. Should the heater/cooler fail, the large volume of water within the system will hold thermal energy for longer than a smaller volume setup.

    An EnFS or NFS or even a front fed DWC will not last nearly as long without power to the pumps. You may have only a couple hours, depending on temperature and relative humidity in the room.

    The Hydro Feed is a 3" main, with a 3" tributary that splits to 2x 2" overflows, giving a max of 1.5" per side, total 3" feed flow cap. The Hydro drain is a 1" tributary to a 2" main, for a maximum 1" drain flow cap. By oversizing the feed 3x, I can ensure the pump operates teh drains at maximum efficiency without worrying about the overflow keeping up. It also keeps a heavy pressure load on the drain lines, thereby increasing positive pressure to the pump, and again, relieving stress on the mechanical parts. 120G of water sits above the drain line, with a total surface area of 220 Sq. Ft. This equals out to a LOT of pressure on top of the drain line, so the pump itself doesn't have to stress about pulling water, more like it facilitates the flow over the "hump".

    The aero system is all 1" though if a cheaper, water resistant ducting can be found, the diameter may increase.

    The piping has been centralized behind the tank to lower the overall profile of the unit an allow the units to be mounted flush along the main array. This is to save space, but does not allow for easy maintenance and disconnect. I'm still working on ensuring I will be able to reach all of the potential Union Bulkheads to be able to extract individual tanks.

    If a valve is installed on the hydro feed line, then the units may be drained first before any disconnections are made. If not, a valve must be placed instead on the hydro drain line, to keep the system from spilling out if I need to disconnect a unit.

    Initially, I was going to install a Union Valve on each line, allowing me to easily disconnect a unit, quickly, without draining it. My idea was to be able to move entire units from one room to another.

    In the main reservoir, a floating fogger below an intake fan with an exhaust pipe to the bay array. Positive pressure forces the fog through the pipes.

    An overflow to the bay array ensures the system doesn't backflow, while always maintaining the minimum water level in the bays.

    The primary DWC pump is positioned at the base of the main res. hooked to a venturi aerator. So, as the water is moved, with a total head height of about 3", allowing the pump to operate with minimum resistance, at maximum efficiency, it sucks fresh air in and descimates it as it re-enters the main res. A propylene glycol solution is pumped through a chilling tower, then dipped into the main reservoir using a heat exchanger. A float valve, connected to a relief reservoir, ensures the main reservoir never drops below a certain point.

    Whadaya Think? I need feedback.

    A single unit prices out at roughly $100, for a 6-site system (about 160 Gal), $1,200.

    It's a sliding scale as you features, but that's the ballpark.
  2. I think you should put some more thought into this... I feel like you're rushing... :rolleyes:

  3. #3 GrapeStreet, May 13, 2011
    Last edited by a moderator: May 13, 2011
    You're probably right...I've still got a lot of angles to cover. I haven't even touched the concepts of nutrient dosage, ph regulation and waste water management.

    However, I'm toying with the concept of setting this up with a vermiculture/aquaculture attached, and run one of the units organically. Still, for the others I'll use a 1/16" venturi attached to the 1/2" top-off float valve in the main res, I can split and control the 1/16" with a valve manifold and regulate how much fertilizer is added when the water is refilled, thus literally "dialing in" the nutrients throughout the cycle.

    The plants are mounted into netpots, dropped through a hole in the lid of the container. These are air tight lids, though I may still need to add a bushing to ensure a complete seal. The lids are easily detached, and the entire root structure, with no medium to weigh it down, can be transported to anther room should the units be immobile. This also allows for "progressive growth tables" where a tilted lighting structure can house regular variable crops such as lettuce, and each tray can be moved from one bay to the next as the younger crop follows. With the extra-wide lipped net-pots, at least for younger plants, you could simply pull the root structure through the drill hole, using the netpot.

    Oh dude, glad you're here. You're my lighting expert. I'm in need of some source materials for a job I'm workin' on.

    You have any good bookmarks/studies regarding the degenerative effects of light on THC. Specifically, I'm trying to figure out which colored vial will be best for storage, with the options of Green, Blue, or Light Amber. My guess is the blue. But I'm looking for some solid sources for information. You're the man on spectrums, so figured I'd see if you had anything to add to the pile.
  4. I'd go with something opaque and air tight... and displace the oxygen with CO2 via [ame=]YouTube - Candletastic - the invisible force (1/9)[/ame]

  5. D. wasn't an option. Fail! :p Any data on the specific spectral effect on metabolism of THC? I'm thinkin' blue'll be the best given the sensitivity to heat.

    Good lookin'. I loved the video. I'd imagine a slight vinegar taste if you were filling masons with V&BS, but the CO2 drip is a good idea in I'm gonna tinker with that. :D
  6. Bump. Still looking for feedback, suggestions, things I didn't see/consider.
  7. I def need to think this thru...but I do have a question..
    will the net pots be right in the top of that?
    and if so 1 per?
  8. Yes, unpictured is the lid to the tote. I've been playing with different configurations. Due to the strict CO MMJ rules on plant count, I'm going to attempt to maximize yield per plant, hence the large root space and surface area. For these it will most likely be 1 netpot per lid/unit.

    However I grow many species, and my vegroom-bay may to contain units with different configurations for different crops, such as lettuce, onions and herbs.
  9. [​IMG]

    Similar to this in style (smaller + full mesh not just bottom), the netpots will be dropped into the lids, the top lip helps weight distribution and makes mounting easier.
  10. thats gonna be one huge fricken plant man...
    Thats allot of nutes bro.... With one plant per id consider going to a smaller tub..
    Butu I like the concept...let me put some thought into it..
  11. #12 GrapeStreet, Jul 15, 2011
    Last edited by a moderator: Jul 15, 2011
    I've got to produce using 12 plants or less, including clones and unfortunately, creating the largest single plant harvests possible is my only answer. Then, I gotta cure it and hash it out so I can also stay under the regulatory weight limits...ugh...

    It's a pain man, but I'm tryin' to stay complaint with state regs and still become self-sufficient. As a caregiver for my wife, I'm now under the scrutiny of the state, so if the MMEDs (that's the MMJ Cops) decide to say "high" I don't end up like Chris Bartkowicz.

    Also, the res size is meant as a nutrient/thermal bank. It mimics the concept of a "tromb wall". By increasing overall volume of the system, changes in the system will be slower and easier to balance and require less energy overall to maintain homeostasis.

    Also, being an organic system, the larger aquaculture helps maintain bacterial cultures.

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