The mission of the Sustainable Environment Agriculture Laboratory (SEAL) is to educate others on methods to improve agricultural sustainability through the understanding and optimization of environmental parameters controlling plant growth. The group focuses on using controlled environment agriculture (CEA) to improve understanding of how plants respond to their environment. Undergraduate, graduate, and community education are core to the success of SEAL. Members work together to establish innovative ways for improving human food availability across the globe. Teamwork and participation are essential to both advance the mission of the lab and improve the lives of each member.
| Micronutrients | ppm | µM |
|---|---|---|
| Boron | 0.08 | 7.0 |
| Chlorine | 0.36 | 0.2 |
| Copper | 0.04 | 0.6 |
| Iron | 0.34 | 6.0 |
| Manganese | 0.16 | 3.0 |
| Molybdenum | 0.01 | 0.1 |
| Sodium* | 0.31 | 0.2 |
| Nickel | 0.01 | 0.1 |
| Zinc | 0.33 | 5.0 |
| Component salt | Formula | mg per L |
|---|---|---|
| Calcium nitrate tetrahydrate | Ca(NO3)2 · 4H2O | 189 |
| Potassium nitrate | KNO3 | 557 |
| Monopotassium phosphate | KH2PO4 | 54 |
| Magnesium sulfate | MgSO4 · 7H2O | 123 |
| Potassium silicate | K2SiO3 | 46 |
| Nitric acid (liquid) | HNO3 | 38 µL |
| Boric acid | H3BO3 | 0.01 |
| Copper-EDTA disodium | Cu-EDTA 2Na | 0.80 |
| Iron-DTPA (Sequestrene 330) | Fe-DTPA | 3.90 |
| Manganese-EDTA disodium hydrate | Mn-EDTA 2Na H2O | 1.22 |
| Sodium molybdate dihydrate | Na2MoO4 · 2H2O | 0.002 |
| Nickel chloride hexahydrate | NiCl2 · 6H2O | 0.002 |
| Zinc chloride | ZnCl2 | 0.41 |
Hydroponic systems can be constructed in many shapes and sizes. Here we describe the pieces required for a small deep-water culture system based on a common 2-gallon bucket. Optional 3D-printed components can be added to improve aesthetics and functionality. The design files for all of the custom pieces can be downloaded from Digital Commons.
Last updated: 4 August 2026
Disclaimer: The instructions provided here are for informational purposes only. Utah State University makes no warranty and assumes no liability as to the designs described in the following sections.
Plastic containers are durable, inexpensive, and easy to source. A 2-gallon-sized bucket will hold 8 L of nutrient solution. The bucket should be opaque to light to eliminate algae growth in the solution. Black buckets are the best, but other colors can be used it they are surrounded by an opaque membrane, such as aluminum foil or foil-lined bubble wrap.
The container serves several purposes: it blocks light from entering the nutrient solution, reduces nutrient solution evaporation, and suspends the plants. Many of the aforementioned 2-gallon buckets come with corresponding lids. These lids must be opaque, just like the bucket, to prevent light from reaching the nutrient solution. Some lids seal tightly onto the buckets, but it is often better to gently set them on top of the bucket instead of sealing them to make plant management easier.
A second option is a customized lid created from extruded polystyrene (XPS). Other types of foam, such as expanded polystyrene (EPS) should be avoided due to their lack of strength. Many hardware stores sell 2' by 2' project panels of 1" thick XPS. This size allows four lids to be created with minimal waste. It is best to avoid larger 4' by 8' XPS sheets as they often come with imbedded score lines that compromise the structural integrity of the lids.
The lids can be created using a CNC router machine, or through the combination of a bandsaw, hole saw, and handheld router. The lid edge can be circular or square, but a circular edge may be more difficult to cut if using a bandsaw. A 'pocket' is routed into the bottom of the lid to help it attach to the bucket rim. One hole is created to add an aeration line, and other holes can be made to hold the plants. An image of a lid cut from XPS foam using a CNC router is shown below:
A bare styrofoam lid works well, but it can be modified to increase its longevity and durability. Covering the lid with a piece of white vinyl protects the surface, reflects light, and simplifies cleaning. Oracal 651 vinyl is UV-resistant, has a tacky back, and is durable under both sunlight (in a greenhouse) and electric lights. The vinyl lid can be cut by hand or with a vinyl cutter, but care should be taken during installation to minimize bubbles. The edges do not have to be cut perfectly as they will be covered with 3D-printed materials.
We have created three pieces to improve the longevity of the container lids. Each can be quickly printed using a 3D printer. Multiple plastics work well, but we have found PETG to be the best compromise between cost and durability.
An outer ring is first created to friction fit onto the styrofoam lid and protect the lid and vinyl edges. The ring is pictured below in an upside down orientation.
Inserts are then created to hold plant collars. They contain a lip on the bottom of the insert to prevent the collar from falling into the nutrient solution.
A similar collar is created to route an air line tube into the container. It lacks the bottom lip.
All lid components friction-fit together without adhesive. The custom lightweight lids are inexpensive, durable, and able to be adapted to many plant species. A completed custom lid is shown below.
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M.S. Plant Science - Graduate Student
Plants, Soils & Climate
Assistant Professor, Controlled Environment Agriculture
Plants, Soils & Climate
M.S. Plant Science - Graduate Student
Plants, Soils & Climate
