The Snyder Industries 500 Gallon Double Wall Liquid Chemical Storage Tank is a 1.9 specific-gravity vertical tank built for aggressive chemical service, pairing a primary storage vessel with an integral secondary containment shell so a primary breach is caught without a separate dike. Molded in white High Density Linear Polyethylene, it stands 81 inches tall on a 53 by 53 inch footprint and holds 500 gallons. Plain water fills it to roughly 4,170 pounds, but the 1.9 SG rating means the walls are engineered to carry contents up to about 7,923 pounds — close to 1.9 times the weight of water, or roughly 3,750 pounds of extra dense-liquid capacity over a standard 1.0 SG tank. That headroom is what lets it store concentrated acids and heavy solutions that would overstress a 1.0 or 1.5 vessel, and at 1.9 it sits at the top of the SG ladder.
Will this double wall tank work for your application?
This is a vertical storage tank with self-contained double wall protection, sized at 500 gallons on a compact 53 x 53 inch base. The 1.9 SG rating is the headline spec for chemical buyers: it defines how heavy a liquid the walls are built to hold. Confirm the full and rated weights against your slab and anchoring plan before install, and review the dimensions on the technical drawing on this page. If you are still narrowing capacity, the Tank Sizing Calculator and Tank Sizing Guide map gallons to footprint and weight for your space.
Chemical compatibility
The tank is molded in HDLPE rated to 1.9 specific gravity. The decision that trips buyers up is not the resin — it is the fitting and gasket material, which must match the chemical, not the tank. The pattern below makes it skimmable: most salts and glycols run PVC fittings with EPDM gaskets; the aggressive oxidizers and acids step up to Viton; and a few have their own rules. Always confirm against the OEM chemical-resistance chart for your exact concentration and operating temperature.
PVC fittings, EPDM gaskets (the workhorse group): Aluminum Sulfate (50%), Calcium Chloride (40%), Ethylene Glycol (100%), Ferric Chloride (50%), Ferric Sulfate (60%), Ferrous Sulfate (20%), Magnesium Chloride (30%), Polyaluminum Chloride, Potassium Carbonate (50%), Potassium Hydroxide (saturated), Sodium Carbonate (30%), and Sodium Thiosulfate (40%). Sodium Bisulfate and Sodium Bisulfite use PVC/PP with EPDM (Sodium Bisulfate, Sodium Bisulfite).
Viton gaskets required (oxidizers and strong acids): Hydrochloric Acid (37%, PVC), Phosphoric Acid (85%, PVC), Hydrogen Peroxide (50%, PVC), Sodium Hypochlorite (under 16.5%, PVC), Hydrofluoric Acid (48%, PP/PVC), and Hydrofluosilicic Acid (26%, PP/PVC). Sulfuric Acid (98%) goes further still, requiring CPVC fittings with Viton.
Special cases: Peracetic Acid (30%) uniquely needs 316SS fittings with Aflas gaskets; Acetic Acid (60%) and Urea Solution (50%) run PP/PVC with EPDM. DEF (32.5%) wants 316SS with EPDM, while Propylene Glycol and Zinc Orthophosphate call for PP/316SS with EPDM. Ozonated Water up to 10 PPM is also compatible on PVC with EPDM. Browse the full Chemical Compatibility Database to confirm your exact service.
The mistake to avoid
The costly error on a chemical tank is matching the resin while ignoring the fittings and gaskets. A 1.9 SG HDLPE wall handles every chemical above, but the milder salts run EPDM and PVC while hydrochloric, phosphoric, and sulfuric acids, hydrogen peroxide, and sodium hypochlorite demand Viton — and peracetic acid demands Aflas, sulfuric demands CPVC. Specify the bulkhead and gasket material to the chemical, or you will have a sound tank leaking at a wrong-gasket fitting. If you are storing concentrated sulfuric or chlorinated chemistry, the double wall containment here is doing the work a separate dike otherwise would. For instrumentation on a contained tank, the tank level gauge selection guide covers radar, ultrasonic, hydrostatic, and magnetostrictive options, and the Snyder Captor double-wall SPCC walkthrough covers 40 CFR 112 containment planning.
This tank ships LTL freight from the Snyder plant in Marked Tree, Arkansas, quoted live to your ZIP — get an exact number with the Freight Cost Estimator or call 866-418-1777 to confirm fittings, lead time, and delivery. If you are weighing other dimensions, compare against these alternate 500-gallon vertical configurations (48 x 68 and 48 x 73), but this 81 x 53 x 53 vessel is the 1.9 SG double wall storage tank built for dense, aggressive chemical service.
