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").;
, 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.
 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).
 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.
 Remember to space plants appropriately so that each receives ample amounts of light.
 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.
 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.



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.
Find a container to use as a reservoir such as a fish tank or a bin/bucket.
If possible, use a fish tank or similar container as your reservoir.
Use a tape measurer to get the length and width of your reservoir.
Do not place StyroFoam in reservoir yet!,
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.
The pump you choose must be strong enough to provide enough oxygen to sustain plants.
Connect the air line to the pump and attach the air stone to the free end.
Set up hydroponics system.
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