The best 20-gallon plastic tank depends on how you plan to use it: choose the RV fresh-water tank for a compact, vehicle-oriented installation, or the portable tank with a spigot and hose for accessible water storage. Nearby-capacity options include a 15-gallon food-grade drum and a 26-gallon square reservoir. Compare capacity, dimensions, fittings, material details, and access before choosing; a tank’s intended use and connection setup matter as much as its gallon rating.
| Tank | Capacity | Best suited for |
|---|---|---|
| RV Fresh Water Tank | 20 gallons | Campers, trailers, and motorhomes |
| Portable Water Tank | 21 gallons | Portable storage with a spigot and hose |
| HOANK Tight Head Drum | 15 gallons | Covered drinking-water storage |
| RomoTech Square Tank | 26 gallons | Utility and worksite liquid storage |
| Elkhart Vertical Tank | 1,000 gallons | Bulk water storage |
20-Gallon RV Fresh Water Tank
This is the most direct match for shoppers looking for a 20-gallon plastic tank for an RV, camper, or trailer. Its cube shape measures 21 by 17 by 14 inches, making those dimensions useful for checking a planned installation space. The listing describes it for potable water used in drinking, cooking, cleaning, and showering.
Best for: RV owners who want a 20-gallon tank designed for fresh-water storage. Why it stands out: Its stated capacity and vehicle-oriented use match the search closely. Limitation: The supplied product details do not specify fitting locations or connection sizes, so confirm plumbing requirements before buying.
Portable 21-Gallon Water Tank
This portable tank offers a stated capacity of 80 liters, or approximately 21 gallons, and measures 28.3 by 13.8 by 15 inches. Its listing describes high-density polyethylene construction, BPA-free material, a spigot and hose, and a 7.9-inch-wide opening. The transparent tank lets users check the water level without opening it.
Best for: Buyers who want near-20-gallon capacity with an accessible opening and dispensing hardware. Why it stands out: Its wide mouth is described as useful for filling and cleaning, while the spigot and hose support water access. Limitation: It is listed as 21 gallons, not exactly 20, and its dimensions may not suit a tight RV compartment.
HOANK 15-Gallon Tight Head Drum
This drum is a smaller alternative for buyers who can accept less than 20 gallons. The listing describes a secure lid, heavy-duty plastic construction, and food-grade, BPA-free material for drinking-water storage. It also identifies 2-inch and three-quarter-inch fittings and describes the drum for water or chemical storage.
Best for: Emergency preparedness or covered storage where 15 gallons is enough. Why it stands out: Its listed food-grade material and secure lid make it a relevant option for water storage. Limitation: The capacity is five gallons below the target, and the listing’s chemical-storage use means buyers should verify suitability for their specific contents and fittings.
RomoTech 26-Gallon Square Tank
This 26-gallon horizontal square reservoir is a larger alternative for farms, job sites, trailers, irrigation, and pressure-washer setups. Its medium-density polyethylene construction is described as rust- and corrosion-resistant, with UV stabilization for outdoor use. The natural translucent color and molded gallon and liter graduations help users monitor the liquid level.
Best for: Utility users who need more than 20 gallons and want visible level markings. Why it stands out: The square form and graduated markings support practical storage and refill planning. Limitation: Its 26-gallon capacity may exceed a 20-gallon target, and the listing describes it for non-flammable liquids rather than specifically confirming potable-water use.
Elkhart Plastics 1,000-Gallon Tank
This vertical tank is not a close capacity match, but it may suit buyers comparing small tanks with bulk storage. The listing specifies UV-resistant HDPE, two 16-inch manway lids, a 1.5-inch fitting at the top, and 2-inch fittings at the bottom. It describes applications such as rainwater collection, agriculture, well-water storage, and emergency use.
Best for: Sites that require large-scale water storage rather than a compact 20-gallon container. Why it stands out: Its stated fittings and access lids support a range of bulk-water setups. Limitation: At 1,000 gallons, it is far larger than a typical RV or portable tank and is not a practical substitute for a 20-gallon model.
Buying Guide: How to Choose a 20-Gallon Plastic Tank
Do you need an exact 20-gallon capacity?
Check the stated capacity rather than relying on a product’s approximate size or intended use. The RV model is listed at exactly 20 gallons; the portable option is 21 gallons. A 15-gallon drum stores less, while the RomoTech holds 26 gallons. Decide whether a small capacity difference is acceptable before comparing other features.
Will the tank fit the available space?
Measure the installation area, including clearance for lids, hoses, and plumbing. The RV tank lists dimensions of 21 by 17 by 14 inches, and the portable model lists 28.3 by 13.8 by 15 inches. Compare all dimensions with the space where the tank will sit, and confirm the orientation required for use.
What fittings and access do you need?
Consider how the tank will fill, drain, and connect to your setup. A wide opening can make filling and interior cleaning easier, while a spigot and hose provide a dispensing option. Listed fitting sizes can help identify possible connection requirements, but verify exact placement and compatibility with your plumbing before purchase.
Is the tank intended for drinking water?
Look for explicit potable, drinking-water, or food-grade language in the listing. The RV tank is described for potable water, and the HOANK drum is described as food-grade and BPA-free. Do not assume that every plastic tank is suitable for drinking water just because it can hold liquid.
Will the tank be stored outdoors?
For outdoor use, compare stated UV-resistance or UV-stabilization details and consider whether the tank’s dimensions and shape suit the location. Check that its listed intended use matches the liquid and storage conditions you have in mind.
Frequently Asked Questions
What is the closest listed match to a 20-gallon plastic tank?
The RV fresh-water tank is listed at 20 gallons and is intended for campers, trailers, motorhomes, and RVs.
Is a 21-gallon tank close enough to replace a 20-gallon tank?
It may be suitable if a one-gallon difference is acceptable and its dimensions and connections fit your setup. The portable option is listed at 21 gallons.
Which option has a spigot and hose?
The portable water tank is listed with a spigot and hose, plus a wide opening for filling and cleaning.
Can any plastic storage tank hold drinking water?
No. Choose a tank whose product details explicitly identify it as suitable for potable or drinking water, or as food-grade for that purpose.
What should I check before installing a tank in an RV?
Measure the available space and verify the tank’s orientation, fitting locations, and connection sizes against the RV’s plumbing requirements.