The Chem-Tainer 40 Gallon Open Top Batch Storage Tank (SKU R183018A) is a compact rectangular polyethylene vessel built for mixing, batching, and short-term holding where you need easy top access. At 18 inches tall on an 18 x 30-inch footprint, it slides under low counters and onto workbenches while still holding a full 40 gallons. The open top gives you room to add product by hand, agitate, or drop in a mixer, and the rectangular form makes better use of tight floor and shelf space than a round open tank of the same volume.
Will it work for your job?
Filled with water, this tank carries about 334 pounds, so plan a flat, fully supported surface that can take that load across the whole 18 x 30-inch base. Each gallon of plain water runs roughly 8.3 pounds; multiply by your fluid's specific gravity to estimate the real filled weight. The polyethylene wall carries a 2.0 specific gravity rating, meaning it is engineered to hold contents up to twice the density of water, or about 667 pounds of rated contents. That 2.0 rating is the highest density step offered in this style, so there is no heavier-rated version to reach for. If you are unsure whether 40 gallons is the right working volume, run the numbers with our Tank Sizing Calculator or read the Tank Sizing Guide before you order.
Fittings and placement
This tank ships as an open vessel with no pre-installed outlet, bulkhead, or drain — you fill and empty from the top, or add your own bulkhead fitting if your process needs one. One upside of that simplicity: there are no gaskets or seals to verify for chemical compatibility, only the polyethylene itself. Because the walls are not domed like a closed vertical tank, even, continuous support underneath matters more; set it on a solid bench, shelf, or pad rather than spanning a gap. For permanent installations where the tank stays full, our guide on concrete pad sizing for above-ground polyethylene tanks walks through building a base that carries the load without flexing. Confirm the outside dimensions against the technical drawing on this page before you frame a cabinet or shelf around it.
The mistake to avoid
The most common error with a rated tank like this is treating the 2.0 specific gravity number as a license to fill it with anything heavy. It sets the density limit, not chemical approval. This is a general-purpose polyethylene batch tank, so match your contents to the material and confirm compatibility for your specific fluid before continuous service. If you are aggregating grey-water, rainwater, or condensate for reuse, our guide on industrial water reuse tank topology covers how open batch and holding tanks fit into a quality-banded storage train.
This open top rectangular tank ships LTL freight from West Babylon, NY, quoted live to your ZIP code. Get an exact number with our Freight Cost Estimator or call 866-418-1777 and we will work up the rate with you.
