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    • Open-Top & Rectangular Plastic Tanks

    Rectangular and Open Top Plastic Tanks for Tight Footprints

    Rectangular plastic tanks put usable volume into spaces a round tank wastes: along a wall, under a bench, inside a cabinet, or on a truck deck. Molded from polyethylene for water and a wide range of process liquids, they are the standard choice when the footprint is fixed and the liquid still has to fit. Open top versions add full access from above for batch work, dipping, and rinsing, with covers available where the contents need protection.

    This guide covers how to choose between rectangular and open top formats, the sizes and options available, and where each fits. Every tank on this page is part of our industrial and chemical storage tanks range, and the full selection is one click away.

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    Why Choose Rectangular Plastic Tanks

    A round tank centers its volume; a rectangular tank fits its volume to the space. That single difference drives most of the reasons buyers specify rectangular plastic water tanks and process tanks:

    • Fixed footprints: equipment rooms, vans and service trucks, under-bench installs, and retrofit spaces where a cylinder will not fit.
    • Wall-flush placement: flat sides sit against walls and against each other, so multiple tanks line up without dead space between them.
    • Low-profile options: shallow rectangles slide under benches and decks where height, not floor area, is the limit.
    • One-piece molded polyethylene: no seams to fail, broad chemical resistance, and no corrosion, indoors or out.

    Square water tanks work the same way with an equal-sided footprint; on this page and in the store, they are part of the same rectangular family.

    Open Top Tanks: Full Access From Above

    An open top tank trades a sealed lid for complete working access. When the job is loading solids, dipping parts, drawing samples, or mixing by hand or machine, the open format is the practical choice. Common uses include:

    • Batch mixing and blending stations.
    • Dip tanks and rinse tanks for parts and components.
    • Quench, wash-down, and collection points in process lines.
    • General open storage where liquid is added and drawn continuously.

    Open top tanks come in both rectangular and cylindrical formats, and many models accept a fitted cover when the process needs one and open access the rest of the time.

    Round or Rectangular: Which Open Top Format Fits

    Choose Cylindrical Open Top When

    • The tank will be mixed mechanically; round walls give even flow with no corners for material to settle in.
    • Complete drain-down and easy cleaning matter more than footprint.
    • Floor space is open and the tank does not need to sit against a wall.

    Choose Rectangular Open Top When

    • The tank must fit a bench, cabinet, alcove, or vehicle with fixed dimensions.
    • Several tanks will sit side by side as a station; flat walls line up with no wasted gaps.
    • Work happens along the tank edge, dipping racks, rinsing lines, or manual loading.

    Where Rectangular and Open Top Tanks Are Used

    • Process and batch work: mixing, blending, and staging liquids between steps. For blended batches that need agitation, see our chemical mixing tanks.
    • Surface treatment: dip, rinse, and wash tanks on plating, cleaning, and finishing lines.
    • Water storage in tight spaces: rectangular plastic water tanks for equipment rooms, vehicles, and under-bench supply.
    • Collection and transfer: catch tanks and holding points where liquid is drawn off as it arrives.

    For processes that need a complete drain between batches, a cone bottom design empties fully; see our cone bottom tanks. For general vertical water storage where footprint is not the constraint, our poly water tanks range covers the standard shapes.

    Rectangular and Open Top Tank FAQs

    Are rectangular plastic tanks safe for drinking water?

    Many rectangular polyethylene tanks are molded from resin suitable for potable water, but ratings vary by model. Confirm the potable rating on the specific tank’s product page or with our team before using any tank for drinking water.

    Can an open top tank be covered?

    Most open top models accept a fitted cover, sold separately or included depending on the model. That lets the same tank run open for batch work and covered for storage. Check the options listed on each product page.

    When should I use a rectangular tank instead of a round one?

    When the space decides the tank: fixed footprints, wall-flush placement, vehicle installs, and multi-tank stations all favor rectangular. When mixing performance and full drain-down matter more than footprint, cylindrical formats have the edge.

    What if the size I need is not in the standard range?

    Custom rectangular plastic tanks can be built to your dimensions. Send the measurements and the liquid you are storing with a quote request and we will confirm the closest standard model or quote a custom build.

    Need a rectangular or open top tank matched to your space and your liquid? Shop the range with live pricing, or send your dimensions for a recommendation.

    SHOP THE RANGE CALL 863-261-8388
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