The Snyder Industries 3000 Gallon ASTM Black Captor Double Wall Tank is a tank-within-a-tank built for sites where a single-wall vessel is not enough containment. Rated to 3,000 gallons in black high density linear polyethylene with a 1.9 specific gravity rating, it pairs a primary storage tank with an integral outer tank so a primary failure stays contained rather than reaching the ground. Footprint is 102 inches by 102 inches with an overall height of 142 inches, so plan the pad and any overhead clearance around those numbers before you order this double wall tank.
Will it work for your site
The 1.9 specific gravity rating is the highest-value spec here: it lets this Captor tank carry contents up to roughly 1.9 times water density without derating, which is why it suits heavier chemistries rather than only fresh water. If your contents run heavier than water, a single-wall or lower-SG tank would be the wrong call. Filled with water alone, expect about 25,020 pounds of liquid weight; at the maximum rated contents density the tank and contents reach roughly 47,538 pounds. Those figures drive your foundation, so the pad must be level, full-perimeter-supported, and rated for the loaded weight at your actual fluid density (25,020 lb on water, up to 47,538 lb at 1.9 SG). Size it with the Tank Sizing Calculator and the Tank Sizing Guide before you pour, matching capacity and freeboard to your draw and refill cycle.
Fittings and access
Per the technical drawing on this page, this tank carries a flange, an 18-inch PE threaded and vented fitting, and a manway with 15-inch access for entry and inspection. The flange and the 18-inch threaded port are your designed tie-in points, and the 15-inch manway access governs which gaskets, bulkhead fittings, and pump or level sensors will physically fit and can be serviced through it, so confirm your inlet, outlet, vent, and instrument hardware match those exact fitting types and that opening before ordering. Reference the technical drawing on this page for fitting orientations and elevations so your tie-ins land where you expect. The vented fitting is a containment-integrity item, not an afterthought: on a closed-top double-wall tank an unvented or blocked vent risks vacuum collapse during fast draw and over-pressure during fast fill, which defeats the whole reason you bought double-wall, so keep the vent clear and sized to your flow rate.
The mistake to avoid
Double wall does not mean maintenance-free. The most common error on a Captor double wall tank is treating the interstitial space as set-and-forget; inspect the annular space and the vented and threaded fittings on a schedule, and never seal off the vent. Because this is a sizing-sensitive vessel, get the freeboard right up front rather than overfilling a tank you sized to the brim. The guide on Snyder Captor double-wall freeboard sizing per ASTM D1998 walks through thermal expansion and density math and the real usable volume, and the HDPE wall-thickness at the vapor-saturated headspace guide explains where premature failures originate and why liquid-side inspection misses them. If your application falls under spill containment rules, the SPCC 40 CFR 112 compliance walkthrough covers how a double wall tank fits the requirement.
This 3000 gallon black double wall tank is built at Snyder plants in Nebraska and West Virginia and ships LTL from the serving plant, with freight quoted live to your ZIP. Get a number for your delivery with the Freight Cost Estimator or call 866-418-1777 to confirm fittings, lead time, and delivery before you order.
