The Chem-Tainer 350 Gallon Vertical Double Wall Chemical Storage Tank (SKU TC5256DC) is a polyethylene secondary-containment tank built for liquid chemical service, rated to a specific gravity of 1.9 in Natural White. The double-wall design puts a contained primary tank inside an integral outer shell, so a leak from the inner tank is captured by the outer wall rather than reaching your floor or berm. It delivers 350 gallons of primary storage plus integral secondary containment on a 52 x 52-inch footprint (about 18.8 sq ft) and stands 56 inches tall - a separate single-wall tank plus a poly catch basin would need materially more floor area and add a second component to inspect.
Will it work for your chemical?
Sizing is where most chemical jobs go wrong, so start with weight, not just gallons. Filled with water, this 350-gallon tank carries roughly 2,919 lb. At its full 1.9 SG rating, the maximum rated contents weigh about 5,546 lb, so your pad, floor loading, and any slab or secondary structure have to be specified for the heavier figure, not the water number. The 1.9 SG rating is the top tier for poly chemical storage and translates to fluids up to about 15.8 lb per gallon - that covers every chemical in the compatibility list below, including 98% sulfuric acid and 50% ferric chloride. Use the Tank Sizing Calculator to confirm working volume against your fill rate, and the Tank Sizing Guide if you are choosing between this vertical double-wall storage tank and a larger size. This is a vertical tank, double wall design built for confined-footprint chemical storage where a single-wall tank plus separate containment will not fit.
Chemical compatibility
This tank is poly construction rated to 1.9 specific gravity. Our resin field for this model is not confirmed between HDLPE and XLPE, and those two resins do not share an identical chemical-resistance profile - confirm the exact resin grade for your chemical and concentration by calling 866-418-1777 before placing the tank into service. The compatibility data below is concentration- and temperature-specific; verify your exact concentration and operating temperature before ordering fittings.
Chemicals compatible with this 1.9 SG poly tank, with the fitting and gasket materials called out for each:
- Acetic Acid (60%) - PP/PVC fittings, EPDM gaskets
- Aluminum Sulfate (50%) - PVC fittings, EPDM gaskets
- Calcium Chloride (40%) - PVC fittings, EPDM gaskets
- DEF (32.5%) - 316SS fittings, EPDM gaskets
- Ethylene Glycol (100%) - PVC fittings, EPDM gaskets
- Ferric Chloride (50%) - PVC fittings, EPDM gaskets
- Ferric Sulfate (60%) - PVC fittings, EPDM gaskets
- Ferrous Sulfate (20%) - PVC fittings, EPDM gaskets
- Hydrochloric Acid (37%) - PVC fittings, Viton gaskets
- Hydrofluoric Acid (48%) - PP/PVC fittings, Viton gaskets
- Hydrofluosilicic Acid (26%) - PP/PVC fittings, Viton gaskets
- Hydrogen Peroxide (50%) - PVC fittings, Viton gaskets
- Magnesium Chloride (30%) - PVC fittings, EPDM gaskets
- Peracetic Acid (30%) - 316SS fittings, Aflas gaskets
- Phosphoric Acid (85%) - PVC fittings, Viton gaskets
- Polyaluminum Chloride - PVC fittings, EPDM gaskets
- Potassium Carbonate (50%) - PVC fittings, EPDM gaskets
- Potassium Hydroxide (Saturated) - PVC fittings, EPDM gaskets
- Propylene Glycol - PP/316SS fittings, EPDM gaskets
- Sodium Bisulfate - PVC/PP fittings, EPDM gaskets
- Sodium Bisulfite - PVC/PP fittings, EPDM gaskets
- Sodium Carbonate (30%) - PVC fittings, EPDM gaskets
- Sodium Hypochlorite (<16.5%) - PVC fittings, Viton gaskets
- Sodium Thiosulfate (40%) - PVC fittings, EPDM gaskets
- Sulfuric Acid (98%) - CPVC fittings, Viton gaskets
- Urea Solution (50%) - PP/PVC fittings, EPDM gaskets
- Zinc Orthophosphate - PP/316SS fittings, EPDM gaskets
- Ozonated Water (up to 10 PPM) - PVC fittings, EPDM gaskets
The mistakes to avoid on this tank are in the gasket and fitting materials. Most services here take PVC or PP fittings with EPDM gaskets, but the exceptions matter: sodium hypochlorite, hydrochloric acid, hydrogen peroxide, phosphoric acid, and sulfuric acid all call for Viton rather than EPDM, and peracetic acid calls for Aflas - an EPDM gasket on those services will degrade. On fitting material, DEF and peracetic acid require 316 stainless rather than PVC or PP, and 98% sulfuric acid requires CPVC rather than standard PVC. Pull the exact concentration, fitting, and gasket spec from the linked chemical page and the full Chemical Compatibility Database before you order any fitting. For instrumentation and overfill protection on double-wall chemical storage, see our guides on tank level gauge selection for chemical service and high-level alarm and cutoff-valve architecture.
Fittings, SPCC, and double-wall containment
Fitting locations, outlet size, and manway placement are not listed in our spec data for TC5256DC - confirm exact placement from the technical drawing on this page or call 866-418-1777 before plumbing the tank. Double-wall storage tanks are the practical way to meet secondary-containment requirements without building a separate berm, which is why they show up so often in SPCC planning. If you are scoping a containment strategy, our SPCC 40 CFR 112 double-wall walkthrough covers how the integral outer wall fits a compliance plan, and our Snyder vs Norwesco vs Chem-Tainer vertical tank comparison covers how Chem-Tainer stacks up if you are weighing brands at a larger size.
This double-wall tank ships LTL from the Chem-Tainer plant in Merced, CA, with freight quoted live to your ZIP - get a number in seconds with the Freight Cost Estimator, or call 866-418-1777 to talk through fittings, gasket selection, and delivery for your chemical. Listed price is before freight.
