Adaptable Hydroponic Method

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Veronica Hardy
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Adaptable Hydroponic Method Table of Contents Advantages of this Adaptable Hydroponic Method: 2 How it Works: 2 Containers: 3 Pumps: 5 Sensors: 5 Tubing: 6 Setting up the system: 7 First Test: 9

1 Adaptable Hydroponic Method Table of Contents Advantages of this Adaptable Hydroponic Method: 2 How it Works: 2 Containers: 3 Pumps: 5 Sensors: 5 Tubing: 6 Setting up the system: 7 First Test: 9 Cycle Interval Settings: 9 Troubleshooting: 10 Audible Alarms and Signals: 11 Specifications: 13 Grow Medium: 14 Lighting: 17 Nutrients: 18 Solar Input: 19 Oct 2016 Page 1 of 19

2 Advantages of this Adaptable Hydroponic Method: Hydroponics allows crop isolation to better control the exposure to weeds, insects, pests, and diseases, while simultaneously reducing labor from those activities. It conserves water by recycling using much less water than terrain farming. The method uses less land per crop yield than irrigated traditional farming. It also reduces pesticide and fertilizer run off by conserving water. This method can be used in remote areas with no electrical or plumbing infrastructure and adaptable to all practical bed sizes. There is no need to install fixed plumbing or modify the containers with drains. There is no need for aerating the roots since the method keeps the grow medium drained. The growing medium can be reused. The noise level is so low that the system is comfortable to operate in the home. How it Works: The method is similar to an Ebb and Flow (a.k.a. Flood and Drain) method with the exception that there is no drain other than the supply tube. The nutrient solution is pumped and fills the bed until the bed level sensor detects the level is high enough. Then the pump stops and the nutrient siphons through the supply tubing and pump back to the nutrient tank. This completes a cycle. The cycle repeats after a programmed interval. Between cycles, the growing medium is wet yet breathable to the plant roots. The sensors work with water as well as a nutrient rich solution. The nutrient solution is sensed to verify that there is enough solution to complete the cycle. There are audible alarms and signals that the controller makes to indicate status and alarms. These can be diagnosed over a phone. Oct 2016 Page 2 of 19

3 Figure 1. This diagram shows the grow bed and nutrient tank. The Controller was designed to be powered from a 12V battery and it has an internal charge regulator for a 20V solar panel to charge the 12V battery. It can also be powered from an AC adapter. The controller can be used with pumps up to 5 amperes DC. If larger pumps are needed, an external switching module can be connected to the controller. Depending on pump size, several bed controllers can be connected to the same battery and solar panel. This a a major cost savings. Figure 2. Hydroponics Controller Kit Containers: The containers can be any practical sizes. Bed containers can be purchased from most Hydroponic stores. A cost effective solution may be to build your own grow beds and nutrient tanks. In this case the bed can be made from a wood box and lined with a heavy plastic sheet. The sheet should be attached to the edge of the wood box. There are many examples and instructions for this. No drain hole is needed. Since the grow medium fills a volume in the grow bed, the nutrient tank can be smaller than the grow bed. Fill the grow bed with grow medium (to the desired level) and then fill up to the grow medium level with water. Siphon out the water into another container to determine the size of the nutrient tank. Oct 2016 Page 3 of 19

4 Figure 3. These are sample grow beds made with this adaptable hydroponic method. Oct 2016 Page 4 of 19

An external 12V DC relay can be used for larger pumps and AC powered pumps. Figure 4. This pump is a 3.8 L/min., 12V brushless DC submersible that is designed for long life.

5 Pumps: Beds can be cycled with a 3.8L/min. pump. Larger beds may require larger pumps. The next size Pump is 6L/min. This pump uses about 1.2 amperes. There is capacity in the controller to power larger pumps up to 5 amps. Pumps used with the controller must be 12V DC powered. An external 12V DC relay can be used for larger pumps and AC powered pumps. Figure 4. This pump is a 3.8 L/min., 12V brushless DC submersible that is designed for long life. It is shown partially disassembled for cleaning. The impeller is sized for debris and particle clearance but it can be clogged. It is recommended to wash the growing medium to reduce particles flowing back from the grow bed. Sensors: Figure 5. These are the Bed and Nutrient Level Sensors. They sense water level by electrical Oct 2016 Page 5 of 19

6 conductivity. These work with a wide range of electrical conductivity. Only one sensor should be used per nutrient tank. If more than one pump is installed in the nutrient tank, then use a bypass resistor for all but the first controller. See more details in the system setup. The Bed Level Sensor is the same as the Nutrient Level Sensor except it does not have the green stripe. Tubing: The tubing supplied with the kit is food and beverage grade per the FDA and the USDA. The tubing includes an anchor disk that is buried at the bottom of the grow medium. Figure 6. This shows the Tubing with the anchor disk and T-Fitting. Oct 2016 Page 6 of 19

Setting up the system: The system is pre-wired with the sensors and pump connected to the terminal block, Unplug the terminal block by pulling it from the controller.

Wire the pump cables to the Pump+ and Pump- terminals on terminal block on the front side of the controller. The Terminals are pluggable.

7 Setting up the system: The system is pre-wired with the sensors and pump connected to the terminal block, Unplug the terminal block by pulling it from the controller. Connect the battery and solar panel to the terminal block. If the system was purchased as a starter kit, then most of the wire connections are already made. Wire the pump cables to the Pump+ and Pump- terminals on terminal block on the front side of the controller. The Terminals are pluggable. Grasp the terminal plug and pull it out and away (unplug) from the controller. This allows for easier connections. Pin 1 Solar Input + (Red) 2 Ground (Solar -, Battery -) (Black) 3 Battery + (Red) 4 Nutrient Sensor - (Black) 5 Nutrient Sensor + (Clear/White) 6 Bed Level Sensor - (Black) 7 Bed Level Sensor + (Clear/White) 8 Pump - (Black) 9 Pump + (Red) Figure 7. This is the terminal block pin-out. Figure 8. Connector and wiring diagram. Oct 2016 Page 7 of 19

The grow bed must be placed above the nutrient tank so that the siphon will work after the bed is filled. There are two sensors included with the controller.

8 The grow bed must be placed above the nutrient tank so that the siphon will work after the bed is filled. There are two sensors included with the controller. The sensor with the green stripe and the pump should be submerged in the nutrient tank. An easy way to fix the sensor in place is to tie-wrap it tho the tube above the pump. Place the tubing anchor with t-fitting at the lowest part of the grow bed. Cover the anchor with grow medium. Fill the grow bed container with grow medium to the desired depth (depending on the root depth expected for the plants). The grow medium can be rock pebble, clay pebbles, vermiculite, or other medium that does not have sand or small particles that would clog the pump. Sand is an example of a medium that would clog the pumps. Rock wool can be used with other medium to hold it in place. If the medium floats (such as clay pebbles or vermiculite), set the sensor to a point deep enough in the medium where the nutrient level does not raise enough to float the medium. The type of grow medium should be selected so that it will not clog the pump. If the pump does become clogged, it can be dismantled and cleaned. There are several small parts that must be saved. There are 4 small screws to remove and save. There are several thrust washers on the main shaft. There is an o-ring to seal the chamber. The impeller can be cleaned with a toothbrush. The motor rotor can be pulled out and cleaned. Take care not to lose any parts. Refer to figure 4. Place the bed level sensor in the bed at the highest level the nutrient should rise to. The bed level sensor can be buried in the grow medium. Do not shove the sensor into the medium as the medium is likely to clog the sensor tip. It is better to dig an opening, position the sensor, and then cover the sensor with grow medium as needed. An easy way to fix the sensor in place is to tie-wrap it to the tube. Figure 9. Bed Level Sensor Oct 2016 Page 8 of 19

Fill the nutrient tank with water until the pump and nutrient sensor are submerged and then continue to fill with enough water to fill the bed to the bed level sensor.

9 Fill the nutrient tank with water until the pump and nutrient sensor are submerged and then continue to fill with enough water to fill the bed to the bed level sensor. Since the grow bed is filled with grow medium, it should take less water (nutrient) to fill the spaces in the medium than if the grow bed was empty. When the grow bed contains grow medium and the water (nutrient) is at the level of the bed sensor, the pump and nutrient sensor should still be submerged. We will test the level in the following steps. First Test: The terminal block should have both sensors, and pump connected. If using a battery and solar panel, they should be connected. If using just a battery and AC adapter, the battery should be connected. If using just the AC adapter, the battery is optional. Plug in the terminal block into the controller. The controller should make some sounds and then turn on the pump. The fill tube will fill with water. The pump will run until the water (nutrient) raises up to the bed level sensor. The nutrient sensor and pump should still be submerged. Add more water if needed. After the bed level sensor detects the water(nutrient) the pump should turn off. The fill tube will be used to siphon the water back into the nutrient tank. This completes the first cycle. Cycle Interval Settings: The default setting for the cycle interval is 3 hours. This is a practical time for most plants. The cycle interval can be changed from 1 hour to 6 hours in ½ hour increments. There is also a test mode for a Cycle Interval of 5 minutes. Uncover the selection switch on the side of the controller. The switch functions like a piano. Press the switches down or up. Figure 10. Cycle Time selection switch. Use a small blade screw driver to set the switches. The following table shows the Cycle Time settings: Oct 2016 Page 9 of 19

10 xxdddd - 5 minutes (Test Mode) xxdduu hrs. xxdudd hrs. xxdudu hrs. xxduud hrs. xxduuu hrs. xxuuuu hrs. (default, Controller comes set at 3 hours.) xxuuud hrs. xxuudu hrs. xxuudd hrs. xxuduu hrs. xxudud hrs. xxuddu hrs. u = up d = down x = does not matter (reserved for future use) Figure 11. Switch Selection table. Troubleshooting: If either sensor appears to be malfunctioning, check the tip for grow medium material, or bent electrodes. The electrodes should be straight and parallel. The sensor may be cleaned with a toothbrush. The resistance of the sensor can be measured with a multimeter. The resistance should be 300K ohms +/- 6K ohms with the terminal block disconnected from the controller. This applies to both the Bed and Nutrient Level Sensors. If the pump does not make noise or vibrate, but you expect every thing else is correct, then remove the impeller cover as shown in Figure 3. Clean the pump and reassemble. Oct 2016 Page 10 of 19

11 Audible Alarms and Signals: The controller makes audible alarms and signals (tones) to help you figure out what the status is. Signal 1 is when the Bed level Sensor was dry and becomes wet. Signal 2 is when the Bed Level Sensor was wet and becomes dry. Alarm 3 is when the Bed Level Sensor is not connected properly. This note scale repeats until the sensor is reconnected. Signal 4 is when the Nutrient Level Sensor was dry and becomes wet. Notice that these tones are one note higher pitch than the signals for the Bed Level Sensor. Signal 5 is when the Nutrient Level Sensor was wet and becomes dry. Oct 2016 Page 11 of 19

12 Alarm 6 is when the Nutrient Level Sensor is not connected Properly. This note scale repeats until the sensor is reconnected. Alarm 7 is when the Nutrient Level is low. This note scale repeats until the Nutrient Level is filled. Signal 8 is at the start of the next cycle. Alarm 9 is when the cycle started but the Bed Level Sensor was not triggered in time. Check the Bed Level Sensor. This note scale repeats until the sensor position is improved and the power is cycled. These tones help you understand the status of the cycles. If you have trouble understanding (or hearing) the alarm or signal, while on a call, you can place your phone over the controller and they can help you diagnose the problem. Oct 2016 Page 12 of 19

13 Specifications: System: Growing Beds Supported: 1 Tubing: Food and Beverage Safe 3/8 ID Power Source, AC Adapter or Battery with charging system (Solar charging option available) Current 13.8V: 1 Pump Running 630mA (varies with bed height) Standby (no pumps or limits on) 70mA Specification for small Pump Flow Rate 3.8 L/min. Input: 9-16V Pressure: Vertical delivery: 2m (6.5ft) Fluid PH:5-10 Current: 500mA@12V Intake: 13.8mm/9mm Dia. Outlet: 7.2mm/5mm Dia. Pump Life span: > 1600rpm~4200rpm Noise: << 30dB Working Temp: 70'C (non-submersed) Envir Temp: <40'C Size(L*W*D): 2.36"x1.3"x1.6" (59mm X 33mm X 41mm) Pump Weight (net): 5.0oz Oct 2016 Page 13 of 19

Pebble Stone: Pebble Stone has been used successfully with many types of plants. Figure 12.

14 Grow Medium: Several types of grow medium can be used. Each grow medium may have advantages for the different types of plants being grown. Pebble Stone: Pebble Stone has been used successfully with many types of plants. Figure 12. This shows Basil seedlings grown directly in stone pebbles. The Nutrient must be added early. Figure 13. Starting Seedlings. These Seed starters can be started indoors with window light. After a week the tiny plants can be installed into the grow medium. Oct 2016 Page 14 of 19

They are best used when the ebbing water level is below the surface of the clay pebbles.

15 Figure 14. Seed starting pods installed into stone pebble grow medium. Clay Pebbles: Clay Pebbles are lighter than Pebble Stone. They float on water. They are best used when the ebbing water level is below the surface of the clay pebbles. Figure 15. This shows A tomato plant growing in clay pebbles. Note the root shoot out. Oct 2016 Page 15 of 19

Vermiculite: The mined product vermiculite can contain asbestos. Modern product has less asbestos but the are still cautions on the product information.

One could assume that wet vermiculite would produce less dust. We have found that vermiculite held moisture better than stone pebbles or clay pebbles. This made it possible to use long cycle times.

16 Vermiculite: The mined product vermiculite can contain asbestos. Modern product has less asbestos but the are still cautions on the product information. That being said, it is a light material that is easy for the plants to grow roots in. Since this is a hydroponic method, most of the time the vermiculite is wet. One could assume that wet vermiculite would produce less dust. We have found that vermiculite held moisture better than stone pebbles or clay pebbles. This made it possible to use long cycle times. One disadvantage is that modern vermiculite tends to be a smaller particle size. The particle size was so small that is passes through a window screen filter. The pump was able to pass small amounts of vermiculite. In continuous use the pump impeller periodically may need to be cleaned more frequently. Figure 16. Shows Vermiculite that has passed through the pump after many cycles. Figure 17. Shows that Vermiculite holds water (stays wet longer) from the hydroponic cycle. Rock Wool: Rock wool is a proven grow medium in hydroponics. Seedlings can be started and grown to adult directly in rock wool. The rock wool can be cut into small shapes and installed in other grow medium to fix in place. Plastic sheet covered rock wool can be used to hold moisture. Oct 2016 Page 16 of 19

17 An alternative to seedlings from dirt would be starting seed from rockwool cubes. To start seeds this way, you will first need to purchase the cubes and follow the instructions. These cubes can be placed near the top of the substrate of your grow bed so that your plants can sprout directly. Make sure to still estimate how much space your plants will need, based upon their adult requirements. Lighting: The type of lighting and proper nutrient will determine the amount of growth. This Hydroponic Method can be used with natural or artificial lighting. Plants need light in the spectral range of 400nm to 700nm. This is also known as it photosynthetically available radiation or PAR. Usually light intensity is measured in lux meters or lumens. However, the PAR measurement is more important in horticulture. Natural Lighting: Natural lighting will product the best results with direct sunlight. Natural sunlight is full spectrum and is about 1000 watts per square meter in intensity. The controller can be used for outside grow beds that are rained on because it auto-drains the excess fill back into the nutrient tank. This assures that the roots do not remain underwater for more than one cycle interval. If the nutrient becomes diluted, it should be reconstituted. Window light is usually side reflected. So it has less intensity than being in direct sun. It may only have direct sunlight in the morning or afternoon. This reduces the sunlight available to the plants. Some plants will still produce acceptable growth. Others will need more time in higher intensity sunlight. Greenhouse Lighting: Lighting in greenhouses is usually filtered by a clear film canopy. Greenhouses also increase heat and humidity. Both are beneficial up to a point. The greenhouse will need venting if temperatures reach over 90 F. Artificial Lighting: Fluorescent and High Intensity Discharge HID Lights Best lumen / watt efficiency mercury vapor, metal halide, high pressure sodium where metal halide is most popular Combination MH and HPS ( Dual Arc ) LED Lights: COB400W COB900W CREE 240W series LED tube T8(4Foot)22W Advantage: Longer Life (50,000 hour typical) HPS Lights: Light is similar to the sun spectrum. Day / Night Balance: Plants may need a ratio of light and dark periods to be changed for the type of plant and the stage of growth. Oct 2016 Page 17 of 19

18 Be aware of the fire danger of high power lighting and the potential to burn the upper leaves of the plants. Some light fixtures require ventilation. Nutrients: There are an enormous number of nutrients available for the Hydroponics market. Contact your local garden center for the best nutrient for your application. Be sure to inform the salesperson that the nutrient is for a hydroponic application. Your grow medium may be a source of mineral for the grow bed. As the system cycles, the nutrient may pick up dissolved minerals from the grow medium. This will change the electrical conductivity of the nutrient solution. Outdoor Grow Beds: In the case of outdoor grow beds, the rain will dilute the concentration of the nutrient solution. Also, there may be quicker growth from algae in the nutrient solution. Based on temperature and rain events, it is necessary to reconstitute the nutrient solution. Indoor and Greenhouse Grow beds: The nutrients for indoor growing may be different from outdoor growing. Check the ph (acidity or alkalinity) of your nutrient and match it to the plants you are growing. You may need to add an acid to increase the acidity. This may be reduced by the alkalinity of the grow medium. An industry standard fertilizer is It has 20% total Nitrogen, 20% available Phosphate, and 20% soluble Potash. It has other trace elements as well. Follow the directions for mixing. There are other formulas that are specific to the plant growth stage. Whether you started your plants from seeds or seedlings, you will need to provide nutrients to your plants. The amount and composition of the nutrients you supply to your plants will vary based on the growth stage that your plant is in. When your plants go from seeds to seedlings, they will require much less nutrient than during any other stages. Once your plants are seedlings, they will be ready to receive fertilizer for vegetative growth. Vegetative growth is the state your plants are in where they grow their leaves and where there stems thicken. This is also the most light intensive phase that the plant will go through, requiring 18 hours on average. After your plants have generated enough leaves and vegetative growth, they will enter the budding phase of growth, which will require a different composition of nutrients. To encourage buds, you will need to switch the composition of nutrients, as well as the amount of light. There are no firm guidelines for this stage, as it strongly depends on the type of plant that you are growing. Lastly, there is the flowering, fruiting stage of development which once again requires a switch in the composition of nutrients. For planning out the levels of nutrients, we at Grower s Gizmos suggest using a nutrient starter kit or pack. These kits are made up of all the nutrients you could need, and come with recipes based on the grow state of your plants. To achieve success, you must carefully follow the recipes and feeding cycle set by the manufacturers. Oct 2016 Page 18 of 19

Solar Input: Built into the controller is a voltage regulator that drops the solar panel voltage from 19-22 volts (in the sun) down to 13.8V which is idea for the charging voltage of 12V batteries.

19 Solar Input: Built into the controller is a voltage regulator that drops the solar panel voltage from volts (in the sun) down to 13.8V which is idea for the charging voltage of 12V batteries. Figure 18. Solar Panel Examples Figure 18 shows a 100 watt solar panel in the foreground and a 5W panel on the table. The 5W panel is suitable to charge a small bed with a 5 Amp / Hour Battery. The 100 Watt panel is suitable to charge a 50 amp / hour battery and power 4 or more grow beds depending on the size and the cycle times. Oct 2016 Page 19 of 19

DID YOU KNOW that the National

Understanding Hydroponics DID YOU KNOW that the National Aeronautics and Space Administration (NASA) is looking at hydroponics as a means of providing food during space exploration? We tend to think of