Hydroponic Lettuce Rack DIY Manual

Transcription

1 Report # SFCC-0001 Hydroponic Lettuce Rack DIY Manual By Daniel Spillers & Adam Cohen May 25, 2016 Version 1.0 1

2 May 25, 2016 Version 1.0 2

3 About the Authors Daniel Spillers I took up a liking to gardening from an early age, using a lean-to greenhouse attached to the south facing wall of our house. During the course of my academic career at Santa Fe Community College, I have achieved an A.A.S. in Greenhouse Management with a strong concentration in business administration. The lettuce rack constructed here is one of the many great projects conducted on the school s premises. I took the liberty in completing this project for my 3 credit hour internship. I highly recommend the encouragement and education of healthy food access and the means to achieve it through a sustainable, economic, and humanitarian scope. Adam Cohen Adam Cohen holds dual bachelor s degrees in Marine Biology and Marine Fisheries from Texas A&M University and has taught mathematics, life and physical sciences, agriculture and entrepreneurship in both private and public high schools for over 12 years. In 2007, Cohen founded Green Phoenix Farms; a company that is focused on providing individuals with the training, materials and designs necessary to produce high quality foods with minimal effort and resource utilization. In August of 2015, Cohen moved to Santa Fe, NM to take over the Greenhouse Management and Operations program at Santa Fe Community College. His commitment to sustainability, natural food and healthy eating, and a concern for the future well-being of communities and the earth as a whole have guided his current efforts to research, develop and educate about Aquaponics. Cohen is committed to developing a method to grow food and aquatic animals in a simple, symbiotic system that can be scaled for back-yard hobby farming or up to large-scale profitable commercial production. As a long-term goal, he envisions an urban agricultural model, which will supply natural fruits, vegetables, herbs and a variety of edible fish and other seafood through a totally selfcontained and sustainable growing system. May 25, 2016 Version 1.0 3

4 System Summary Hydroponics The word hydroponic is Latin of origin meaning working water. Hydroponics is a method of growing plants in a nutrient rich water solution, where dissolved mineral salts can be absorbed through the roots of the plants without soil. Description This design is a hybrid between a Deep Water Culture (DWC) system and a Nutrient Film Technique (NFT). DWC system design is flexible, and allows the desired raft design to float on top of the troughs. Most designs of this type have a specific crop in mind, for which the appropriate plant production spacing will be built into the rafts. The NFT system utilizes a long-thin channel or gully to re-circulate a water/solution through to grow plants in. A thin layer of water/solution with dissolved mineral-salts in it provides the roots of the plant the right amount of dissolved oxygen, water, and nutrients. Multiple channels or gullies are usually lined up next to each other according to the desired crop, density, and requirements. The system described in this manual measures 8 long x 4 wide x 8 tall, and is intended as a conventional hydroponic system. This system utilizes a 3 ½ trough that is similar to a DWC system, given that food-safe rafts will float inside the trough. It is also similar to a NFT system, in that it only uses 1 2 of water/solution on each shelf. The 36-hole Beaver Plastics Lettuce Production Rafts are recommend for this system. These measure 48 x 24 x 1 (LxWxH), and are made of hard composite food-safe Styrofoam. However, they will need to be trimmed down in order to fit the troughs in this system. The system uses a 110-gallon food-safe tote as a reservoir for the hydroponic mineral-salt solution needed for plant growth. A pump will then supply the solution through a constructed PVC pipe system to each shelf equally. A submersible pump, approximately 500 GPH, is recommended for this system. An 18 watt single outlet commercial air pump, approximately 70 LPM, is recommended to power several airstones in the reservoir for increased dissolved oxygen content in the nutrient solution. This will ensure that the plants have the necessary oxygen needed for optimal growth. May 25, 2016 Version 1.0 4

5 System Capabilities This system will use only 32 square feet for the ground footprint. Optimally it would be advantageous for a walkway of roughly three (3) feet around the system. This spacing will allow for easy access to all plants and will optimize the efficiency of both transplanting and harvesting. As described in this manual, this system will contain three (3) shelves that each measure 4 x 8. Each of these shelve can hold four (4) production rafts. Using the suggested plant spacing of 36 plants per raft, each shelf will hold 144 plants, while the system will hold a total of 432 plants. Using artificial lighting on a hour (per day) schedule, it is possible to show a 28-day grow cycle on lettuce. This means that roughly 25% of the total plants can be harvested every week. Using the densities above, this means that this system can produce approximately 108 head of a lettuce a week. The total water volume of the system, contained in the three shelves and the 100- gallon sump tank, is approximately 200 gallons of water. It will be necessary to add between 25 and 50 gallons of water per week, based on climate (ambient humidity) and temperature. While feeding schedules will vary significantly depending on the specific type/recipe of nutrients used, we have found that we can get excellent growth by adding a charge of nutrients on a three-week interval. May 25, 2016 Version 1.0 5

6 Supplies Needed L x 4 W x 21/32 Thick Pressure Treated Plywood x 4 x 96 Studs 3. 3 (1 lb. Pack) 2 ½ Decking Screws L x 36 W x 20 H Gallon Heavy Duty Oval Tank PVC Pipe *Note* There will be a small portion leftover PVC Pipe *Note* There will be a small portion leftover ½ PVC Pipe *Note* There will be a small portion leftover PVC Standard T Fittings PVC 90 degree Elbow PVC Snap Fitting 3 way Reducing Couplings PVC Standard T Fittings PVC 90 degree Elbows /2 Reducing Couplings ½ PVC 90 degree Elbows ½ PVC End Caps ½ PVC Ball Valves 18. PVC Glue and Primer x 4 6 Bulb T5 Light Fixtures (Recommended: Agrobrite T5 4 fixture w/ 6 bulbs) Timer (use one for each shelf 4 fixtures per timer) Aerator (~ 70 LPM) Airstones Airline Hose (1/4 ) Water Pump (~ 500 GPH) Tools Required 1. Chop Saw or Skill Saw 2. At Least 1 18 volt Lithium Ion Compact/Cordless Drill / Driver 3. 3/16 General Purpose Drill Bit 4. Tape Measure 5. 1 ¼ Hole Saw 6. Carpenter s Knife 7. Carpenter s Level (2 or larger) May 25, 2016 Version 1.0 6

7 Cut and Prepared Lumber 1. Pieces A = 16 2 x 4 x 20 Studs 2. Pieces B = 10 2 x 4 x 48 Studs 3. Pieces C = 10 2 x 4 x 93 Studs 4. Pieces D = x 4 x 96 Studs 5. Pieces E = L x 4 W x ½ Thick Plywood A D B C E May 25, 2016 Version 1.0 7

8 Step 1: Assemble Base Frame, Top Frame, and 3 Shelves *NOTE* It is suggested to predrill all lumber before screwing together, in order to prevent splitting. 1. Use 2-48 (B) to cap 2-93 (C) to form a total of 5 frames as indicated above. Each frame should have a final measurement of 48 x 96. ** NOTE: The ends of the frame will be on the outside of the 93 pieces. 2. Place 1 sheet of 21/32 thick plywood (E) directly on 1 assembled shelf frame and fasten down in each corner creating an 8 L x 4 W x 3.5 D shelf. 3. Using a total of 14 screws, continue to fasten down bottom of the shelf. Use 4 screws for each 4 W side and 3 additional screws will be needed and evenly spread apart to fasten the 8 L. (Predrilling is recommended for this step.) 4. Repeat previous three steps 4 more times to build a total of five (5) frames. ** Only three (3) will have a plywood base ** May 25, 2016 Version 1.0 8

9 Step 2: Assemble the Frame Structure and Supports. 1. Using 2 screws per upright, fasten the 4 upright supports (D) to the base frame. Be sure to hit each of the base frame s 2 x 4 s. ** Note: Use a Carpenter s Level to ensure that all uprights are straight and level. May 25, 2016 Version 1.0 9

10 2. Place 4 small supports (A) in each corner and fasten with 2 screws (top and bottom). The shelf supports (A) need to be directly on the base frame and on the inside of the upright supports (D). Be sure the 2 screws are evenly spaced apart and screwed in from the inside of the upright supports (D). Install the screws from the inside of support A, and into D. 3. Insert 1 st shelf on top of the shelf supports (A) and square it up using the Carpenter s Level, making sure the corners of the shelf frame are directly over the supports (A), and in line with upright supports (D). 4. Screw the shelf in from the outside of the upright supports (D) at each corner using 2 screws. Make sure to hit each of the shelf s 2 x 4 s. Then screw an additional 2 screws above and below the shelf screws. Be sure to center and evenly space the 2 additional screws as indicated in the image to the right. May 25, 2016 Version

11 5. Repeat steps 2 4 another two times to complete the shelf structure. May 25, 2016 Version

12 6. Screw the top frame in from the outside of the upright frame supports at all 4 corners using 2 screws for each being sure to hit each of the top frame s 2 x 4 s. *Note* Inner supports are not needed for top frame light support. May 25, 2016 Version

13 Step 3: Place 110 Gallon Tank Underneath Lettuce Rack 1. Place tote underneath lettuce rack s bottom shelf in through either of the rack s 8 lengths. 2. Be sure to pull the tote closest to the side that is the easiest to access and then center. May 25, 2016 Version

14 Step 4: Create Drains and Line Shelving 1. Using 1.25 hole saw, drill through each shelf 6 from the desired drainage end. Be sure to center each drain between the 4 widths of each shelf. 2. Apply food-safe liner lengthwise using a stapler and carpenter s knife. ** SFCC has a great video on how to install liner. View it at 3. Carefully cut holes in liner where the PVC bulkhead fittings go. May 25, 2016 Version

15 Step 5: Size and Piece together PVC Drainage System *NOTE* Always measure, cut, and piece PVC pipe together before gluing. *NOTE* Purple PVC glue primer will not wash out of clothing or anything else it touches. *NOTE* The cubes connecting PVC pipe together at intersections, 90 degree angles, and at ends represent PVC pipe fittings corresponding with size of pipe being used. 1. Temporarily fasten 6 x 2 drainpipe to the front upright support with flexible metal nail strapping. This will make measuring pieces easier and more accurate. 2. Use the 2 3- way PVC fitting at bottom of upright drainpipe. 3. Cut a 4 section of the 2 PVC pipe. Use this piece with the 3-way fitting in a way that allows water to drain directly into the reservoir. May 25, 2016 Version

16 4. Attach a 90-degree elbow (2 ) at the end of the 4 drainpipe. Make sure this piece is pointed down into the reservoir. 5. Cut and insert an 18 length of the 2 PVC pipe and use it as the downspout for the drain. 6. Repeat steps 1-5 for the water supply line, however, for this line use 1 PVC pipe and fittings in place of the 2 pipe and fittings used for the drainage system. The 1 supply line will have to be measured and cut depending on the dimensions of the water pump being used. May 25, 2016 Version

17 7. Cut 2-3 segment of 1 PVC and insert into the bottom of the bulkhead. Use the small segment of PVC to connect degree PVC elbow directly to the bulkhead. 8. The next section of 1 PVC needed will be approximately 9 ½ long. Insert this piece into the 1 90-degree elbow and attach 1 more 1 90-degree elbow at the end of 9 ½ length. 9. Measure and cut 1 PVC pipe approximately 21 long and connect the drain down pipe to shelf s drain. Use reducing couple from 2 3 way drain to connect shelf s drain to the system s drain down pipe. May 25, 2016 Version

18 10. Repeat instructions for Step and connect to the 2 PVC T connectors needed. Use reducing couples as needed to adapt 1 PVC pipe to 2 PVC T connector. If desired, use 2 PVC end cap to close off drain downpipe. May 25, 2016 Version

19 Step 6: Size and Piece together PVC Input System 1. Measure and cut 1 PVC pipe approximately 20 long and insert into the 1 PVC 90-degree elbow on the pump input line. 2. Attach 1 PVC T fitting on the end of the newly added 20 piece and point the T inward and over the shelf. 3. Cut a 2 segment of the 1 PVC pipe and insert into the T fitting pointing out and attach 1 PVC 90-degree elbow pointing down. 4. Use 1 ½ reducing coupling in order to downsize to ½ PVC pipe. 5. Measure, cut, and insert 7 ½ segment of ½ PVC pipe into coupling and then attach ½ ball valve. May 25, 2016 Version

20 6. Next, cut ½ PVC pipe approximately 7 ½ long and insert into ball valve. Attach ½ PVC 90-degree elbow to the end of the newly added segment. 7. Insert approximately 43 ½ of ½ PVC into the elbow and then attach ½ PVC end cap. 8. The newly added 43 ½ length will need to be perforated to distribute an even and directional flow of water/solution to the shelf. This completes the first shelf s irrigation line. 9. Measure and cut 1 PVC pipe approximately 23 long and insert into the first shelf s T fitting and repeat sub steps Repeat sub step 9 to complete the third shelf s irrigation line. 11. Insert short section of 1 PVC pipe to the last 1 PVC T fitting and attach 1 PVC end cap. May 25, 2016 Version

21 Step 7: Hang and Situate Lighting *Note* Use smaller 1 Screws to Anchor Lightning in Place 1. Start at end of the system and measure in 15 from the end of the frame. Now, find the center vertically on the 2 x 4 and insert a screw to support the first light fixture. 2. From this point, measure another distance of 20 and insert the screw for the next light fixture. The next two light fixtures will be the same spacing of 20 thereafter. 3. Repeat this process for all 3 shelves. 4. The top shelf s lighting will have to be fasten down securely to the top frame by inverting the light s cables and then screw them into the 2 x 4. May 25, 2016 Version

22 Step 8: Final Lateral Supports 1. Use 96 2 x 4 and screw directly in the middle of the lettuce rack to evenly support shelves weight when filled with 2 of water/solution. 2. Repeat 1 more time to the other side of the lettuce rack. May 25, 2016 Version

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