Building a DIY Aquaponics System with IBC Totes

Building a DIY Aquaponics System with IBC Totes

Aquaponics, the combination of aquaculture (raising fish) and hydroponics (growing plants in water), is one of the most efficient and sustainable food production methods available to home gardeners and small-scale producers. And the most popular vessel for building a backyard aquaponics system is the humble IBC tote. With a single 275-gallon IBC, a few plumbing fittings, and a weekend of work, you can build a fully functional system that produces both fresh fish and vegetables year-round. Here in Utah, where water conservation is a way of life, aquaponics is particularly appealing because it uses approximately 90 percent less water than traditional soil gardening.

This guide will walk you through the entire process, from selecting and preparing your IBC to cycling the system and maintaining it for long-term success. We have seen hundreds of our recycled IBCs turned into aquaponics systems by Utah families and small farms, and we have collected the lessons learned into this comprehensive resource.

What Is Aquaponics and Why Does It Work?

Aquaponics creates a symbiotic loop between fish and plants. Fish produce waste in the form of ammonia. Beneficial bacteria, primarily Nitrosomonas and Nitrobacter, colonize the grow media and convert that ammonia first to nitrite and then to nitrate. Nitrate is an excellent nitrogen-based fertilizer that plants absorb through their roots. The plants clean the water, which is then returned to the fish tank. It is a closed-loop ecosystem where each component supports the others.

The beauty of this system is its efficiency. You feed the fish, and the fish feed the plants. There is no chemical fertilizer to buy, no soil to till, no weeding, and dramatically less water consumption than conventional gardening. A well-balanced aquaponics system loses water only to evaporation and plant transpiration, typically requiring you to top off just 1 to 3 percent of total volume per week.

Why IBC Totes Are Perfect for Aquaponics

IBC totes have become the go-to vessel for DIY aquaponics systems for several compelling reasons:

• Volume: A 275-gallon IBC provides enough water volume for a meaningful fish population while being compact enough for a backyard installation.
• Two-for-one design: By cutting the IBC strategically, you get both a fish tank and a grow bed from a single container.
• Built-in structure: The steel cage provides rigidity and support, eliminating the need to build a separate frame.
• Existing plumbing: The bottom valve port provides a ready-made drain connection for the fish tank.
• Cost: A recycled IBC from Salt Lake IBC costs $80 to $150, a fraction of what custom tanks or commercial aquaponics kits cost.
• Food-safe material: HDPE is a food-grade plastic that will not leach harmful chemicals into the water.

Selecting the Right IBC

Not every IBC is suitable for aquaponics. Here is what to look for:

• Previous contents: This is the most critical factor. Choose an IBC that previously held food-grade or non-toxic products. IBCs that contained food ingredients (corn syrup, vinegar, fruit juice, vegetable oil) are ideal. IBCs that held cleaning products, detergents, or non-toxic agricultural products are acceptable with thorough cleaning. Never use an IBC that held pesticides, herbicides, solvents, or industrial chemicals for aquaponics. Chemical residues can leach from the HDPE and harm fish and plants.
• Bottle condition: Look for a clear or translucent bottle without cracks, deep scratches, or significant UV degradation (yellowing and brittleness). Minor surface scratches are fine.
• Cage condition: The cage should be structurally sound with no broken welds. Cosmetic rust is acceptable, but structural corrosion is not.
• Color: For aquaponics, you actually want to paint or cover the fish tank portion to block light. Algae growth in a clear IBC can become a major maintenance headache. Some people prefer IBCs with white or opaque bottles, but any color works if you plan to cover it.

At Salt Lake IBC, we keep food-grade IBCs separated in our inventory specifically because of demand from the aquaponics and gardening community. Ask us about food-grade options when you visit our Woods Cross location.

Cutting the IBC: Fish Tank Bottom, Grow Bed Top

The standard IBC aquaponics design involves cutting the IBC approximately one-third of the way from the top. The upper portion (approximately 12 inches deep) becomes the grow bed. The lower, larger portion (approximately 30 inches deep) becomes the fish tank. Here is how to do it:

Tools You Will Need

• Reciprocating saw (Sawzall) with a fine-tooth metal blade and a separate blade for plastic
• Angle grinder with a cut-off wheel for the cage
• Measuring tape and marker
• Drill with hole saw bits (for plumbing penetrations)
• Safety glasses, gloves, and hearing protection

Step-by-Step Cutting Process

• Step 1: Measure and mark your cut line on the cage. For a standard 275-gallon IBC that is approximately 46 inches tall (bottle only), mark at approximately 12 to 14 inches from the top. Use the horizontal cage tube as a guide if it aligns near your desired cut height.
• Step 2: Cut the cage first. Use the angle grinder to cut through the steel tubes. Cut all four sides. Remove the upper cage section.
• Step 3: Cut the HDPE bottle. Use the reciprocating saw with a plastic-cutting blade. Follow your marked line, cutting slowly and steadily. The plastic will flex, so having a second person hold the wall steady is helpful.
• Step 4: Flip the cut top section over. It now becomes a shallow tray that will serve as the grow bed. It sits on top of the cage of the lower fish tank section, supported by the remaining cage frame.
• Step 5: Reassemble the upper cage section around the grow bed to provide structural support. You may need to cut and weld (or bolt) cage pieces to create a frame that holds the grow bed securely above the fish tank.

The result is a two-tier system: the grow bed on top filled with grow media, and the fish tank below. Water is pumped from the fish tank up to the grow bed, percolates through the media (where bacteria process the fish waste and plant roots absorb nutrients), and then drains back to the fish tank by gravity.

Plumbing: Bell Siphon and Pump Sizing

The Bell Siphon

The bell siphon is the elegant mechanical heart of a flood-and-drain aquaponics system. It uses no electricity and has no moving parts. It works by harnessing the physics of siphon action to automatically flood the grow bed with water and then rapidly drain it, creating the wet-dry cycles that plant roots and beneficial bacteria need.

A bell siphon consists of three components: a standpipe (sets the maximum water level), a bell (an inverted tube that fits over the standpipe), and a media guard (a perforated outer tube that keeps grow media away from the bell). When the pump fills the grow bed, water rises around the bell. When it reaches the top of the standpipe, water begins flowing down the standpipe. The bell traps air and creates a siphon effect that rapidly drains the entire grow bed. Once the water drops below the bottom edge of the bell, air enters and breaks the siphon. The bed then refills. This cycle repeats automatically, typically every 15 to 25 minutes.

For a standard IBC grow bed, a 1-inch standpipe with a 3 or 4-inch diameter bell and a 6-inch diameter media guard works well. Use PVC fittings throughout. Many excellent bell siphon building tutorials are available online, and the total materials cost is typically under $20.

Pump Selection

You need a submersible pump in the fish tank that can move water up to the grow bed at a sufficient flow rate. For a single-IBC system, the general guideline is to cycle the fish tank volume through the grow bed once per hour. With a fish tank volume of approximately 175 to 200 gallons (the remaining lower portion of the IBC after cutting), you need a pump that delivers at least 200 gallons per hour at the head height from the fish tank to the top of the grow bed (typically 3 to 4 feet).

A pump rated at 300 to 400 GPH at the required head will provide a comfortable margin. Small submersible pumps in this range (like the Hydrofarm Active Aqua 400 or similar) cost $25 to $50 and consume only 20 to 40 watts of electricity, costing roughly $2 to $4 per month to operate continuously.

Fish Species for Utah's Climate

Utah's climate presents specific challenges for aquaponics: cold winters with temperatures well below freezing, hot summers, and significant daily temperature swings. Fish selection must account for these conditions, especially if your system is outdoors or in an unheated greenhouse.

• Tilapia: The most popular aquaponics fish worldwide, tilapia are fast-growing, hardy, and excellent eating. However, they are a warm-water species that thrives between 75 and 85 degrees Fahrenheit and will die below 55 degrees Fahrenheit. In Utah, tilapia require a heated system for winter operation, either indoors, in a heated greenhouse, or with a tank heater. For outdoor summer-only systems, tilapia can work from May through September. Note that tilapia may require a Utah Division of Wildlife Resources permit depending on your location and setup.
• Trout: Rainbow trout are an excellent cold-water alternative perfectly suited to Utah's climate. They thrive in water temperatures of 50 to 65 degrees Fahrenheit and can tolerate temperatures down to near freezing. Trout grow well in aquaponics systems and are a prized food fish. The challenge is that trout need cooler water, so they struggle in Utah's summer heat. A summer shade structure or chiller may be necessary. Trout also require higher dissolved oxygen levels than tilapia.
• Bluegill and sunfish: These native-range fish are incredibly hardy, tolerating temperatures from near freezing to over 85 degrees Fahrenheit. They are legal without permits in most Utah jurisdictions. Bluegill grow more slowly than tilapia and are smaller at harvest, but they are tough, disease-resistant, and excellent for beginners.
• Channel catfish: Another warm-water option that tolerates a wide temperature range (50 to 85 degrees Fahrenheit). Catfish are bottom feeders, naturally suited to the tank environment, and grow to edible size relatively quickly. They tolerate lower water quality than trout, making them more forgiving for beginners.
• Koi and goldfish: If you are more interested in the plants than the fish, ornamental koi or large goldfish are extremely hardy, tolerate a wide temperature range, and provide excellent nutrient production. They are a great choice for a decorative aquaponics garden without the complexities of food fish management.

Plants That Thrive in Aquaponics

Aquaponics supports a remarkable range of plants. In a media bed system (which is what the IBC design creates), the grow media provides both root support and biological filtration surface area. The best plants for beginners and for Utah's growing season include:

• Leafy greens: Lettuce, kale, Swiss chard, spinach, and arugula are the easiest and most productive aquaponics crops. They grow fast, require modest nutrients, and thrive in Utah's spring and fall temperatures.
• Herbs: Basil, mint, cilantro, chives, parsley, and oregano all perform exceptionally well. Basil, in particular, is almost legendary in aquaponics for its vigorous growth.
• Tomatoes and peppers: These heavy feeders need a well-established system with robust nutrient levels (meaning enough fish) but produce abundantly once established. They do best during Utah's warm summer months.
• Cucumbers and squash: Excellent warm-season producers. Provide trellising above the grow bed for vine support.
• Strawberries: A surprisingly good aquaponics crop. They produce continuously in Utah from late spring through fall.

Cycling the System

Before adding fish, your system needs to develop its bacterial colony. This process, called cycling, establishes the Nitrosomonas and Nitrobacter bacteria that convert ammonia to nitrite to nitrate. Cycling typically takes 4 to 6 weeks and should not be rushed.

• Fishless cycling (recommended): Add ammonia to the system (pure ammonia from a hardware store, no surfactants) to simulate fish waste. Target 2-4 ppm ammonia. Test daily with a freshwater test kit. You will see ammonia spike, then nitrite will appear, then nitrate. When ammonia and nitrite both drop to zero within 24 hours of an ammonia dose, cycling is complete.
• Fish-in cycling (less recommended): Add a small number of hardy fish and let their waste drive the cycling. This is stressful for the fish and requires daily monitoring and frequent water changes to keep ammonia below toxic levels.

Maintenance Schedule

• Daily: Feed fish (2-3 times daily, only what they consume in 5 minutes). Visually check water flow, pump operation, and fish behavior. Remove any dead plant material.
• Weekly: Test water parameters (pH, ammonia, nitrite, nitrate). Top off evaporated water with dechlorinated water. Check pH and adjust if needed (optimal range 6.8-7.2 for most systems).
• Monthly: Clean pump intake screen. Inspect plumbing for leaks. Check bell siphon operation. Prune and harvest plants.
• Seasonally: Prepare for temperature changes. In Utah, this means adding heaters or insulation for winter operation, or transitioning to cold-season crops and cold-tolerant fish.

Common Mistakes to Avoid

• Overstocking fish: A common beginner mistake. For a 175-gallon fish tank, start with no more than 15-20 small fish and scale up as the system matures. The general rule is 1 pound of fish per 5-10 gallons of water.
• Skipping the cycling phase: Adding a full fish load to an uncycled system will result in toxic ammonia spikes that can kill the entire population in days.
• Using the wrong grow media: Expanded clay pebbles (Hydroton) or lava rock are ideal. Do not use regular gravel from a garden center, as it can alter pH and may contain limestone that will drive pH too high. Avoid any media that is chemically reactive.
• Neglecting pH management: The system naturally tends toward acidity over time due to the nitrification process. Regular pH monitoring and occasional adjustment with potassium carbonate or calcium carbonate is essential.
• Ignoring light management on the fish tank: A translucent IBC will grow aggressive algae if light reaches the fish tank water. Paint the outside of the fish tank section or wrap it with reflective insulation to block all light.
• No backup power: If the pump stops for more than a few hours, dissolved oxygen drops and fish can suffocate. A battery backup or at minimum a battery-operated air pump is cheap insurance.

An IBC aquaponics system is a wonderful project that teaches biology, engineering, and sustainable food production all at once. Start small, be patient with the cycling process, and enjoy watching the ecosystem you have built come to life. Stop by Salt Lake IBC in Woods Cross to pick up a food-grade tote for your build.