Build a Homemade Hydroponics System

Building your own water works system is quite simple and can be fun, if you know how to follow instructions. This type of system would be best used for water loving plants such as lettuce.

Steps

  1. Choose the type of system you want to build. Your choices include:
    • Water Culture. This is a low cost, easy-to-build option. It results in your plants being suspended in water by a StyroFoam platform. The water will be filled with a nutrient solution. You can grow 5-6 plants per {{safesubst:#invoke:convert|convert}} water culture system.
    • Multi Flow. This is a medium cost, fairly difficult-to-build option. It relies on gravity to flood plant trays with water and nutrient. You can use a timer and float switch to control water levels. You can grow many plants at a time with this system.
    • Ebb and Flow. This is a low-cost, moderately easy-to-build system. Your plant tray is put on top of a reservoir and connected to the reservoir with tubing. A water pump pumps water and nutrients to the plants. Excess liquid is returned to the reservoir for later use. You can grow a fair amount of plants with this system.
  2. Gather all the materials you need for this project. They are listed in the "Things You'll Need" section.

Water Culture

  1. Find a container to use as a reservoir such as a fish tank or a bin/bucket. If it's not light-proof, the reservoir should be painted black (or covered with thick black trash bag if you want to reuse a tank).
    • Allowing light to enter the reservoir will promote the growth of algae, which disrupts the growth of other plants by stealing oxygen and nutrients.
    • It is a good idea to use a reservoir that is the same dimensions (length x width) from top to bottom (Example: Top is 36" x 20" and bottom is 36" x 20").
  2. If possible, use a fish tank or similar container as your reservoir. Spray paint tank (if translucent) black and let dry. Before painting, apply a strip of painters' tape vertically from the top edge to the bottom. When the paint dries, remove the tape and use the unpainted space to show you how much water is in the reservoir.
    • Creating this line, however, is not necessary as you can determine how much water is in the reservoir simply by noticing how far down the floater (StyroFoam) has sunk.
    • Adding the line gives a more accurate and convenient view of the nutrient solution level.
  3. Use a tape measurer to get the length and width of your reservoir. Measure from inside of the reservoir from one end to the other. Once you have the dimensions, cut the StyroFoam 1/4" (inch) smaller than the size of the reservoir.
    • For example, if your dimensions are 36" in length and 20" in width you should cut the StyroFoam to 35 3/4" x 19 3/4".
    • The StyroFoam should fix nicely, with just enough room to adjust to water level changes.
    • If the reservoir tapers off at the bottom (the bottom is smaller in dimension than the top) the floater (StyroFoam) should be 2"-4" smaller than the reservoir (or more if necessary).
  4. Do not place StyroFoam in reservoir yet! First, you need to cut the holes for the net pots. Put the net pots on the StyroFoam where you want to place each plant.
    • Using a pen or pencil, trace around the bottom of the net pots. Use a sharp tool such as a knife or box cutter to follow the trace lines and cut the holes for pots. (KIDS!!! Get help from an adult.)
    • On one end of the StyroFoam (any end), cut a small hole for the air line to run into the reservoir.
  5. The number of plants you can grow will depend on the size of the garden you build and the types of crops you want to grow. Remember to space plants appropriately so that each receives ample amounts of light.
  6. The pump you choose must be strong enough to provide enough oxygen to sustain plants. Ask for advice choosing a pump at your local hydroponics supply store. Tell them the size of your reservoir (In gallons - 2, 5, 10 gallons, etc.) and they should be able to make a recommendation.
  7. Connect the air line to the pump and attach the air stone to the free end. The air line should be long enough to travel from the pump into the bottom of the reservoir or at least float in the middle somewhere so the oxygen bubbles can get to the roots. It also must be the right size for the pump you choose. Most pumps will come with the correct size air line.
    • To make your best approximation, use a one gallon bucket/bottle or any container of known capacity and fill the reservoir. Remember to count how much it takes to fill the reservoir and you will know the capacity of your reservoir.
  8. Set up hydroponics system.
    • Fill reservoir with nutrient solution.
    • Place the StyroFoam in tank.
    • Run the air line through the designated hole/notch.
    • Fill the net pots with growing medium and place one plant in each pot.
    • Put the net pots into the designated holes in StyroFoam.
    • Turn on/plug-in pump and start growing with your fully-functional, homemade hydroponics system.

Multi Flow

  1. Place your six pots on a stable surface. Be sure that the surface is not tilted, or the system will not work properly.
  2. Connect them with the PVC fittings and tubes. If the container you have is designed for a multi flow system, it should automatically turn the power on and off as the water levels in the container change. Thus, this is a safer and more efficient flood/drain system than those used in ebb and flows (see next section)
  3. Put the plants in the small plant trays. Ensure that everything is working properly.

Ebb and Flow

  1. Choose a location for your reservoir. Put the plant tray on top of the reservoir. If it doesn't fit well, set up a support structure to keep it level.
  2. Install the fill/drain system in the tray. Connect tubes to the water pump and place it inside the reservoir. Double check that overflow goes back into the reservoir, rather than spilling out around it.
  3. Connect the pump timer.
  4. Place the plants and their pots in the tray.



Nutrient Strengths

Different plants prefer different concentration of nutrients. Growing different plants with similar requirements will help ensure the best growth. The concentration of nutrients is measured as Conductivity Factor (CF). The more nutrients dissolved in the solution, the more conductive it becomes.

  • Beans - CF 18-25
  • Beetroot - CF 18-22
  • Broccoli - CF 18-24
  • Brussels Sprouts - CF 18-24
  • Cabbages - CF 18-24
  • Capsicum - CF 20-27
  • Carrots - CF 17-22
  • Cauliflower - CF 18-24
  • Celery - CF 18-24
  • Cucumbers - CF 16-20
  • Leeks - CF 16-20
  • Lettuce - CF 8-12
  • Marrows - CF 10-20
  • Onions - CF 18-22
  • Peas - CF 14-18
  • Potatoes - CF 16-24
  • Pumpkin - CF 18-24
  • Radish - CF 16-22
  • Spinach - CF 18-23
  • Silverbeet - CF 18-24
  • Sweetcorn - CF 16-22
  • Tomatoes - CF 22-28

Tips

  • Make sure to protect your reservoir from light in order to discourage the growth of algae, which can disrupt plant growth by diverting oxygen.
  • A homemade hydroponics system like this is not ideal for a large scale production or commercial usage. This particular system plan does not offer a way to conveniently change nutrient solution. An extra container would be required to hold the floater while you change the solution.
  • Plant growth usually reduces the pH of the water drastically, so be sure to check pH with a dropper kit.
  • Preferably, use a reservoir that is rectangular in shape. The top and bottom sides should ideally be of the same dimensions to promote even plant growth and nutrient distribution.
  • Be careful when cutting Styrofoam with a box cutter or knife. Although Styrofoam is a relatively soft material and does not require deep cuts, a small misstep can still result in a lot of pain for your fingers.

Warnings

  • The hydroponics system works best with plants that require a lot of water, such as lettuce. Those plants have an easier time with water and nutrient uptake. If your crop is not as absorbent, it may not grow well in this reservoir.

Things You'll Need

  • External pump: You will also need a switch system for multi flow to automatically regulate water levels.
  • Tubing: This should be PVC for multi flow systems and an air tube for water culture. any normal tubing will work for ebb and flow.
  • Waterproof bin, bucket, fish tank to use as a reservoir: If you are building a multi flow system, it should be vertical to allow for better flood control. It should also have a controller unit to plug the water pump into.
  • StyroFoam if you are implementing a water culture system: An inch or so thick should be fine.
  • Pots: Mesh Pots are ideal for water cultures, whereas plastic nursery pots are acceptable for ebb and flow systems.
  • Plant trays: You will create your own from StyroFoam if you are planning on implementing a water culture system. Otherwise, you should have at least six trays for a multi flow system or a plastic/plastic-covered metal ebb and flow tray for an ebb and flow system.
  • Growing medium - Rockwool, Grow rocks, etc.
  • Hydroponics nutrients - (Grow formula, Bloom formula, Supplements, Ph)
  • Black spray paint, paint (only required if reservoir is transparent)
  • Sharp object - Knife, box cutter, scissors (This is not a task for minors)
  • Air stones for a water culture system
  • A flow/drain system for ebb and flow. This is a group of drains and pipes that allows water to be recycled into the reservoir.
  • Make sure you keep your pots on stable surfaces, or you may end up with uneven plant growth.

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