7 Best High-Capacity Water Storage Tanks For Greenhouse Irrigation
Keep your plants hydrated with our top 7 high-capacity water storage tanks for greenhouse irrigation. Find the perfect reliable solution for your garden today.
A dry greenhouse during the heat of July spells disaster for even the most resilient tomato crop. Managing water reserves is the difference between a thriving seasonal harvest and a total loss of labor and investment. Selecting the right storage tank transforms unpredictable rainfall or well-water limitations into a reliable, consistent irrigation foundation.
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Norwesco 500 Gallon: Best Overall Capacity
The Norwesco 500-gallon tank hits the “Goldilocks” zone for most hobby farmers, offering enough volume to sustain a standard 10×20 foot greenhouse through a week of peak heat. Its vertical footprint is efficient, allowing for placement in a corner without sacrificing valuable planting row space.
Built with high-density polyethylene, this tank handles the pressure of full capacity while resisting the degradation caused by fluctuating seasonal temperatures. The translucent finish makes water-level monitoring an easy, quick visual check during a morning walk-through.
This is the definitive choice for the hobbyist who wants a “set it and forget it” solution. If the greenhouse scale is moderate and the objective is reliability without excessive plumbing, the Norwesco is the most logical investment.
Ace Roto-Mold 200 Gallon: For Tight Spaces
Small greenhouses often prioritize every square inch for soil beds, leaving little room for heavy equipment. The Ace Roto-Mold 200-gallon tank addresses this constraint with a slim, space-saving design that tucks neatly against walls or behind shelving.
Despite the lower capacity, its portability makes it ideal for setups where the tank might need relocation as crops rotate or as light conditions shift throughout the year. It serves as an excellent supplemental reservoir for targeted hand-watering or as a secondary tank in a multi-unit irrigation system.
Do not overlook this unit simply because of the smaller volume. For those managing a boutique space or micro-greens, the footprint efficiency outweighs the need for a massive, space-consuming reservoir.
Bushman 1000 Gallon: Rainwater Harvesting Pro
When reliance on well water needs to be minimized, the Bushman 1000-gallon tank becomes a primary asset for rainwater collection. Its reinforced walls are engineered specifically to withstand the weight of larger volumes, making it a rugged centerpiece for a greenhouse water-management strategy.
The design incorporates a focus on long-term storage, often featuring superior UV protection to prevent the internal breakdown of the plastic. Pairing this with a roof-gutter system turns every storm into a functional irrigation resource for the entire growing season.
If the goal is self-sufficiency and the greenhouse is large enough to warrant a significant catchment area, this tank is a top-tier performer. It is a substantial commitment, but it pays dividends in reduced utility costs and sustainable water usage.
Enduraplas 300 Gallon: Most Versatile Pick
The Enduraplas 300-gallon tank finds a perfect balance between capacity and mobility. It is robust enough to act as a permanent fixture, yet light enough to move with standard farm equipment if the greenhouse setup changes over a few seasons.
What sets this model apart is the build quality of its fittings and its resistance to cracking under impact. Many hobby farmers find that this specific capacity serves as the ideal “buffer” tank between a main well-fed reservoir and the final irrigation lines.
Choosing this tank is a smart move for farmers who prefer a modular system. It is reliable, easy to transport, and offers enough capacity to carry a greenhouse through a few days of intense irrigation without being cumbersome to manage.
Poly-Mart 530 Gallon: Best Algae Prevention
Algae growth is the silent enemy of greenhouse irrigation, clogging emitters and clouding the water. The Poly-Mart 530-gallon tank features a dark, opaque construction designed to block out nearly all sunlight, which effectively prevents the photosynthesis required for algae blooms.
Beyond its anti-algae properties, this tank features a thick, durable wall construction that handles the pressure of heavy water cycles without bowing. It provides a clean, clear supply of water that keeps drip lines and irrigation valves functioning at peak performance.
If the greenhouse is situated in a high-light area and the maintenance of drip irrigation systems is a concern, this tank is the superior choice. It eliminates the need for expensive chemical treatments or frequent scrubbing of the tank interior.
Snyder 700 Gallon: For Large Greenhouse Needs
As a hobby operation scales toward semi-professional, water requirements often outpace standard tanks. The Snyder 700-gallon tank provides a significant jump in capacity without requiring a massive footprint expansion, making it a favorite for larger greenhouse footprints.
This tank is designed for longevity, using heavy-duty resin that holds up against years of seasonal temperature swings. Its height is optimized to provide sufficient head pressure for gravity-fed systems, which is essential when electricity is not readily available for pumps.
Investing in this unit indicates a commitment to long-term growth. If current expansion plans involve adding more rows or expanding into hydroponic systems, starting with this capacity prevents the need for an expensive upgrade down the road.
Behlen 150 Gallon Stock Tank: Durable & Simple
Sometimes the best tool for the job is the simplest one. The Behlen 150-gallon stock tank is not just for livestock; it serves as an excellent, low-maintenance open reservoir for greenhouses that require frequent refilling or easy dipping access.
Because the top is open, it allows for easy checking of water quality and rapid refilling from a hose or catchment pipe. The galvanized steel or heavy-duty poly versions are virtually indestructible, handling accidental knocks from wheelbarrows or equipment without blinking.
This is the right choice for the pragmatic farmer who wants to spend more time planting and less time managing plumbing. If the irrigation needs are modest or involve periodic hand-watering, this is the most cost-effective, durable solution on the market.
Sizing Your Tank: How Much Water Do You Need?
Calculating the correct tank size starts with the daily water requirements of the specific crop and the total square footage of the greenhouse. As a rule of thumb, most vegetables require at least one gallon of water per square foot of soil during high-heat weeks.
Consider the potential for “dry days” during mid-summer. A tank should hold at least three to four days of total water demand to account for heatwaves or unexpected pump failures.
- Small scale (under 100 sq ft): 150–200 gallons is sufficient.
- Medium scale (100–300 sq ft): 300–500 gallons is the ideal range.
- Large scale (over 300 sq ft): 700–1000 gallons ensures security.
Setting Up Your Tank for Gravity-Fed Irrigation
Gravity-fed irrigation relies on the physics of “head pressure.” For every foot of height the tank is raised above the irrigation emitters, the pressure increases by approximately 0.43 PSI. This is vital for drip tapes and low-flow emitters that require a consistent, albeit low, amount of pressure to function.
Constructing a sturdy, level platform is non-negotiable. A 500-gallon tank weighs over 4,000 pounds when full; a sagging base can cause the tank to warp or fail, leading to leaks and potential structural damage to the greenhouse floor.
Always install a ball valve at the base of the tank for easy flow control. Using a sediment filter between the tank outlet and the main irrigation lines will further protect your emitters from potential debris that settles at the bottom of any storage container.
Tank Maintenance: Keeping Your Water Clean & Safe
Clean water is essential for preventing the spread of soil-borne pathogens. Even in closed tanks, organic matter can enter through catchment systems or open lids. Inspect the tank interior annually and use a soft brush to remove any biofilms that have formed on the walls.
If the tank is used for rainwater, ensure the gutter screens are cleared of debris before every rainy season. This prevents the primary source of contamination—decaying leaves and bird droppings—from entering the reservoir in the first place.
For those using well water, occasional testing for pH and mineral buildup is recommended. If the water becomes murky or develops a strong odor, it is a sign that the storage system needs a thorough flush and sanitization with a weak, food-safe bleach solution.
Consistent water management is a hallmark of a successful hobby farmer, turning the uncontrollable factors of weather into a managed asset. By selecting a high-capacity tank that matches your specific greenhouse needs and keeping it clean, the foundation for a productive growing season is secure. With the right equipment in place, the focus remains where it belongs: on the plants and the harvest.
