The Enduraplas 400 Gallon White Horizontal Leg Tank (SKU THF00400W) is a 400-gallon polyethylene leg tank built to haul and store liquid loads where a stable, low-profile footprint matters. Molded in natural white poly, it measures 74 inches long by 46 inches wide by 37 inches high, so it drops into a trailer, skid, or truck bed without towering over the rig. The horizontal body and integrated legs keep the center of gravity low, which is exactly what you want when a 400 gallon tank moves down the road full.
Will it work for your job?
This tank carries a specific gravity rating of 1.9, meaning the wall thickness is engineered for liquids substantially denser than water. Plain water fills the 400-gallon capacity at roughly 3,336 pounds, and at the full 1.9 SG rating the tank is built to handle up to about 6,338 pounds of contents. That headroom is the reason a horizontal leg tank like this shows up under fertilizer applicators and chemical haul trailers rather than just water transport. The 46.0 x 74.0 inch footprint and 37-inch height let you mount it where overhead clearance and weight distribution are tight - but at a full 1.9-SG load this tank places roughly 6,338 pounds on its mount, so verify your trailer, skid, or bed rating before you fill it. If you are unsure whether 400 gallons is the right size for your run, the Tank Sizing Calculator and Tank Sizing Guide walk you through matching capacity to load and vehicle. For dimensional detail, see the technical drawing on this page.
Chemical compatibility
This is a polyethylene tank carried on our records as HDLPE (unverified) with a 1.9 specific gravity rating. Because the resin code is not confirmed, settle the HDLPE-versus-XLPE question before committing this tank to chemical service - crosslinked and linear poly behave differently with aggressive chemistries. Every chemical below requires matched fittings and gaskets per the OEM chemical-resistance chart, which is concentration- and temperature-specific; check each compatibility page for the pairing rather than assuming a single hardware spec covers the list. Most of these run on PVC fittings with EPDM gaskets: Acetic Acid at 60% (PP/PVC), Aluminum Sulfate at 50%, Calcium Chloride at 40%, Ethylene Glycol at 100%, Ferric Chloride at 50%, Ferric Sulfate at 60%, Ferrous Sulfate at 20%, Magnesium Chloride at 30%, Polyaluminum Chloride, Potassium Carbonate at 50%, Potassium Hydroxide (saturated), Propylene Glycol (PP/316SS), Sodium Bisulfate (PVC/PP), Sodium Bisulfite (PVC/PP), Sodium Carbonate at 30%, Sodium Thiosulfate at 40%, Urea Solution at 50% (PP/PVC), and Zinc Orthophosphate (PP/316SS).
The chemicals that need upgraded hardware
A separate group on the chart will eat through standard PVC/EPDM and demands upgraded fittings and gaskets: Hydrochloric Acid at 37% (PVC/Viton), Hydrofluoric Acid at 48% (PP/PVC, Viton), Hydrofluosilicic Acid at 26% (PP/PVC, Viton), Hydrogen Peroxide at 50% (PVC/Viton), Phosphoric Acid at 85% (PVC/Viton), Sodium Hypochlorite below 16.5% (PVC/Viton), Sulfuric Acid at 98% (CPVC/Viton), DEF at 32.5% (316SS/EPDM), and Peracetic Acid at 30% (316SS/Aflas). Specifying EPDM and PVC by reflex on any of these is the fast path to a failed gasket and a leaking outlet. The OEM chart also rates this tank for ozonated water up to 10 PPM on PVC fittings and EPDM gaskets - an oxidizer that behaves differently from the concentration-based entries above, so treat it as its own case and confirm conditions before running it. Review the full chemical compatibility reference before you order.
The mistake to avoid
The trap with a leg tank is treating specific gravity as a formality. The 1.9 SG rating is not permission to fill any liquid to the brim - it is the design ceiling, and 1.9 is the highest-rated wall available in this size and style. If your product runs heavier than 1.9, this tank is not the answer; call 866-418-1777 and we will work out denser-service options rather than overrunning what the wall and outlets were built for. The other half of the trap is the resin: the HDLPE-versus-XLPE question above is not cosmetic, because the same shell carries very different chemical tolerance depending on how it was molded. For agricultural use, our guides on applicator and leg tanks for fertilizer, portable utility tanks and the 49 CFR ag exemption, and fertilizer-blend tank stratification cover the DOT scope and mixing issues that catch operators off guard.
This 400 gallon Enduraplas horizontal leg tank ships LTL on a freight carrier directly from the Neche, North Dakota plant, with freight quoted live to your ZIP - get your exact number with the Freight Cost Estimator or call 866-418-1777. Shipping from North Dakota keeps Upper Midwest and Plains deliveries efficient; tell us your ZIP and we will land the LTL quote for you.
