Vertical Closed Top Storage Tanks

Closed-top vertical plastic tanks: choose according to the liquid and installation

A closed-top vertical tank is used to store liquid in a stationary, above-ground installation. Its flat bottom requires a base that properly supports the entire tank. Its shape makes use of available height while limiting the floor space required. It can serve as a water reserve, a buffer tank or storage for a compatible liquid in an agricultural, food-processing or industrial setting.

Capacity is a starting point. Before choosing from the tanks shown here, we also check the liquid, its specific gravity and temperature, the dimensions of the installation site, and how the tank will be filled, emptied and maintained.

VFN or VFA: what should you compare?

Most closed-top vertical tanks are offered with a specific gravity rating of 1.5 or 1.9. A 2.2 rating is also available by special order for the VFA series. Availability and configuration must be confirmed for the model you need.

Specific gravity does not tell the whole story

We are sometimes asked for a “stronger” tank without being told what it will contain. A specific gravity rating of 1.5, 1.9 or 2.2 is one selection criterion, but it does not establish chemical compatibility. For a fertilizer, treatment solution or other chemical, we need to know the exact liquid, its concentration and temperature. Gaskets, bulkhead fittings and valves must also be suitable for that liquid.

For water intended for human consumption or a food product, we confirm the requirements applicable to the model and the components in contact with the liquid. A material that meets FDA requirements does not, by itself, validate the entire installation. Potable water hoses must also be selected for their intended use.

What to plan before ordering

Access, base and maintenance

A tank can have the right capacity yet be impossible to install in the planned location. We check the route to the site, available height, space around the tank and access to its lid. The base must support the tank bottom according to the model’s requirements. Our page on tank delivery, installation and use outlines precautions to consider.

A closed-top vertical tank is intended for stationary, above-ground storage. If the liquid must be transported, compare horizontal tanks designed for transport or caged IBC totes.

Filling, venting and draining

One costly mistake we see in the field is choosing the tank before determining where the pump and piping will connect. Check which connections and outlets are present on the model, then plan those required for the project. This is especially important for VFA tanks, whose vent, outlet and graduations must be requested according to the liquid being stored and the planned installation. The lid, vent, drainage and access needed for inspection are all part of this review. Agrico can assist you in selecting the tank and its accessories before ordering.

If more complete gravity drainage is essential, consider closed-top cone-bottom tanks. If access from above is insufficient, compare open-top vertical tanks. For a project requiring secondary containment, double-wall tanks warrant a separate evaluation.

Frequently asked questions

Can a closed-top vertical tank be moved while full?

No. The models in this category are intended for stationary storage. Storage capacity does not mean a tank is approved for transport.

Are all models suitable for potable water?

No. The selected model and all components in contact with the water must meet the requirements of the intended use, particularly when the water is intended for human consumption.

Does a specific gravity rating of 1.9 or 2.2 guarantee chemical compatibility?

No. The tank’s specific gravity rating and its chemical compatibility are separate checks. The liquid’s concentration and temperature, as well as the materials of accessories in contact with it, must also be considered.