# Spray tank selection: capacity, plumbing and service access

URL: https://leafwrit.com/us/sprayer-tank-selection/
Reviewed: 2026-10-29

Choose a spray tank as part of the complete sprayer system. Check filling and cleaning access, corrosion resistance, agitation, drain, outlets and liquid-level indication. Buying only by the advertised gallon capacity leaves those operating questions unresolved.

## Tank material and lid

Tank construction must resist corrosion from the herbicide formulations it will hold. The lid seal contains liquid; the vent prevents a vacuum. For replacement lids, compare the model, seal and vent with the manufacturer's parts information.

Check corrosion resistance and the condition of protective coatings on mild-steel tanks. Liquid pesticides may affect pump gaskets, plunger caps and impellers, so these belong in the compatibility review.

## Agitation

Maintain uniform concentration as the tank empties for uniform application. Dry formulations can float or settle; agitation-nozzle placement affects how thoroughly they mix.

The agitation mechanism is bypass circulation, hydraulic jets or mechanical stirring. Hydraulic jets sit near the tank bottom and connect to the pump's pressure side. Mechanical agitators use blades or propellers on a shaft.

Provide enough pump capacity for the nozzles and the hydraulic agitator together at the desired pressure. Insufficient mixing can produce uneven delivery, while excessive agitation may cause foaming and interfere with pump or nozzle operation.

## Filling, draining and cleaning access

A tank needs a large filling opening, space for a filling strainer and a large drain.

## Outlets, pump and isolation

Size tank outlets for the pump capacity. A shutoff valve isolates stored liquid while other sprayer components are serviced.

A closed tank vent, obstructed lines or screens, hose kinks and pump problems can stop delivery, so a low-output symptom can involve several components.

Use reinforced suction hose to resist collapse. Inspect suction and pressure plumbing for kinks, abrasion and surface deterioration.

Centrifugal pumps require a suitable mounting or priming arrangement. Dry running or restricted inlet or outlet flow can damage pumps.

Dual-tank plumbing must support agitation and adequate withdrawal from both tanks.

## Liquid-level indicator and drain

Protect an external gauge against breakage.

## Sprayer tank size in gallons: ATV, RTV, trailer and tractor tanks

Tank capacity follows the class of machine. Newly designed ATV sprayers hold 16, 24 or 40 gallons, with optional front tank add-ons for many ATV models. A recreational-type vehicle (RTV, or Gator) carries a larger amount, with a capacity of up to 150 gallons. Truck- and trailer-mounted sprayers for treating invasive plants often have a tank of 100 to 250 gallons. Tractor-mounted tanks hold 200 to 600 gallons of spray solution per tank. A 40 gallon tank is one of the ATV sizes, a 100 or 150 gallon tank falls in the RTV and truck-or-trailer range, and a 300 or 500 gallon tank falls in the tractor-mounted range. Booms, wands and tow-behind units for these sizes are in the [ATV and UTV sprayer guide](/us/atv-utv-sprayer-selection/).

## How many acres a 10 to 500 gallon sprayer tank covers

The area a tank covers is the gallons in the tank divided by the calibrated gallons per acre (GPA). A 500 gallon sprayer tank on a sprayer calibrated at 30 GPA covers 16.6 acres, because 500 ÷ 30 = 16.6. The same division gives the table below for a 10, 15, 20, 25, 30, 40, 50, 60, 100, 200, 300 or 500 gallon tank at three common rates; replace the rate with the GPA of your own calibration.

| Tank | Acres at 10 GPA | Acres at 20 GPA | Acres at 40 GPA |
|---|---|---|---|
| 10 gallon sprayer tank | 1 | 0.5 | 0.25 |
| 15 gallon sprayer tank | 1.5 | 0.75 | 0.38 |
| 20 gallon sprayer tank | 2 | 1 | 0.5 |
| 25 gallon sprayer tank | 2.5 | 1.25 | 0.63 |
| 30 gallon sprayer tank | 3 | 1.5 | 0.75 |
| 40 gallon sprayer tank | 4 | 2 | 1 |
| 50 gallon sprayer tank | 5 | 2.5 | 1.25 |
| 60 gallon sprayer tank | 6 | 3 | 1.5 |
| 100 gallon sprayer tank | 10 | 5 | 2.5 |
| 200 gallon sprayer tank | 20 | 10 | 5 |
| 300 gallon sprayer tank | 30 | 15 | 7.5 |
| 500 gallon sprayer tank | 50 | 25 | 12.5 |

A 15 gallon ATV sprayer or a 25 gallon sprayer with boom therefore treats a small plot per fill, while a 300 gallon tank sprayer or a 500 gallon sprayer tank on a tractor treats a field block. Four fills of a 25 gallon tank sprayer, or 2.5 fills of a 40 gallon tank sprayer, hold the volume of one 100 gallon tank.

### Spray tank sizes in litres: 50, 100, 400, 500 and 1000 L

A US gallon is 3.785 litres, so a 50 L spray tank holds 13.2 gallons, a 100 L tank 26.4 gallons, a 400 L tank 105.7 gallons, a 500 L tank 132.1 gallons and a 1000 L tank 264.2 gallons. Divide by your calibrated gallons per acre as above: at 20 GPA a 50 L tank covers 0.7 acre, a 100 L tank 1.3 acres, a 400 L tank 5.3 acres, a 500 L tank 6.6 acres and a 1000 L tank 13.2 acres. Against the tank classes above, a 50 L tank is just below the 16 gallon ATV size, a 100 L tank is an ATV size, 400 and 500 L tanks fall in the 100 to 250 gallon truck-and-trailer range, and a 1000 L tank falls in the 200 to 600 gallon tractor-mounted range.

### Spray tanks for trucks, a yellow sprayer tank and a poison spray tank

Spray tanks for trucks, the tanks that sit in a truck bed, are chosen by the same checks as any sprayer tank: material, lid, agitation, drain and outlets. A yellow sprayer tank is only a color choice; check the material and the agitation, not the color. A poison spray tank is a tank that carried a pesticide, so keep it for that use and rinse it before any other liquid goes in.

## Poly, fiberglass, vertical and saddle spray tanks

Plastic (poly) sprayer tanks, fiberglass spray tanks, space saver and vertical spray tanks, a saddle tank on an ATV, a pull behind spray tank, a truck bed sprayer tank, spray tanks for tractors and a spray tank on wheels all go through the same checks as any other tank: resistance to the formulation, a lid with a vent, a large filling opening and drain, agitation and a protected level gauge. Keep a sprayer hand wash tank with clean water at the filling place for rinsing hands and gloves. A 12 volt tank sprayer, a cordless tank sprayer and a compressed air tank sprayer are small-tank units for hand work; the acreage per fill follows from the same division.

## Next step

See the [application-equipment checklist](https://cms.ctahr.hawaii.edu/epp/Education/Study-Guide-Packets/APC-PAS/APC-PASUNIT3) for tank and plumbing requirements.

### How do I choose a spray tank?

Match the actual mixture and machine, then compare capacity, material, openings, plumbing, agitation, level indication and mounting instructions.

### Are all 25 gallon sprayer tanks interchangeable?

The gallon description does not establish dimensions, supports, fittings or usable volume. Compare the exact tank specification with the equipment.

### What should I check for an ATV sprayer tank?

Establish the vehicle and mounting specifications for the complete loaded configuration and keep those checks separate from tank-load arithmetic.

### Does a larger sprayer tank solve poor agitation?

Tank size alone does not establish mixing performance. Assess the pump, return arrangement, tank geometry and formulation needs together.