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Alpha 21 Gallon RV Fresh Water Tank - 386BLANK
Upgrade your RV's fresh water storage with the Alpha 386BLANK, a premium 21-gallon fresh water tank engineered to meet or exceed OEM standards. This rotational molded tank features FDA-approved polyethylene construction, seamless one-piece design, and superior durability that outlasts factory-installed tanks. With compact dimensions of 39" x 16" x 8", this tank is perfect for smaller RVs, campers, or installations where space is limited.
Why Choose the Alpha 386BLANK Fresh Water Tank?
FDA-Approved Polyethylene for Safe Drinking Water
Your family's health matters. The 386BLANK is crafted from high-quality, FDA-approved polyethylene that's specifically certified for safe drinking water storage. Unlike some factory tanks that use questionable materials, this Alpha tank ensures your water stays clean, fresh, and safe to drink mile after mile.
Seamless One-Piece Rotational Molded Construction
Engineered without seams, joints, or weak points, this rotational molded tank delivers superior strength and leak-proof reliability. The seamless construction eliminates the failure points common in welded or multi-piece tanks, giving you peace of mind that your water stays where it belongs.
Stain, Corrosion, and Rust Resistant
Built to last for years of hard use, the 386BLANK resists stains, corrosion, and rust even in harsh conditions. The durable polyethylene material stays clean and functional season after season, ensuring your water stays fresh and your tank stays dependable.
Compact Design for Space-Conscious Installations
With 21 gallons of capacity in a compact 39" x 16" x 8" footprint, this tank is ideal for smaller RVs, camper vans, teardrop trailers, or any installation where space is at a premium. Get reliable water storage without sacrificing valuable compartment space.
Superior to Factory-Installed Tanks
Many RV manufacturers cut corners with thin-walled, inferior tanks. The Alpha 386BLANK is built tougher than typical OEM tanks, offering enhanced durability and longevity that makes it the smart choice for replacements or upgrades.
Technical Specifications
- Part Number: 386BLANK
- Capacity: 21 gallons
- Dimensions: 39" Length x 16" Width x 8" Height
- Material: FDA-approved polyethylene
- Construction: Seamless rotational molded one-piece design
- Tank Type: Fresh water storage
- Weight: Lightweight yet durable construction
- Dimensional Weight: 30 lbs
- SKU: 386BLANK
- Barcode: 779386000002
- Manufacturer: Alpha Systems
- Condition: Brand new OEM quality
Perfect Applications for This Fresh Water Tank
- Small RVs and camper vans
- Teardrop trailers and compact travel trailers
- Horse trailer fresh water supply
- Marine vessel potable water storage
- Off-grid cabin and tiny home water systems
- Emergency water storage for mobile applications
- Custom builds where space is limited
Installation and Compatibility
The Alpha 386BLANK is designed as a direct replacement for OEM fresh water tanks in many smaller RV models. Before ordering, measure your existing tank compartment to ensure proper fitment. The compact 39" x 16" x 8" dimensions make this tank versatile for tight installations.
Installation requires basic plumbing skills and standard RV water system fittings. The tank features standard inlet and outlet ports compatible with most RV fresh water systems. Professional installation is recommended for optimal performance and warranty compliance.
Comparison: Find Your Perfect Alpha Fresh Water Tank Size
| Model | Capacity | Dimensions (L x W x H) | Best For | View Details |
|---|---|---|---|---|
| 386BLANK | 21 gallons | 39" x 16" x 8" | Compact RVs, space-limited installations | Current Product |
| 388BLANK | 40 gallons | 39" x 18" x 14" | Similar length, nearly double capacity | View Details → |
| 502BLANK | 42 gallons | 48" x 24" x 12" | Larger capacity, standard installations | View Details → |
Pro Tip: Measure your tank compartment carefully before ordering. Account for inlet/outlet fittings and allow clearance for installation and removal. The 386BLANK's compact size makes it perfect for tight spaces.
Explore More Fresh Water Tank Options
Browse our complete selection of 40 Gallon RV Fresh Water Tanks or shop all RV Fresh Water Tanks to find the perfect capacity for your needs.
What RV Owners Are Saying
With a 4.5 out of 5-star rating based on 4 verified customer reviews, the Alpha 386BLANK consistently earns praise for its quality construction, leak-proof performance, and superior durability compared to factory tanks. Customers love the peace of mind that comes with FDA-approved materials and authentic Alpha quality.
Frequently Asked Questions
Is this tank FDA-approved for drinking water?
Yes, the 386BLANK is manufactured from FDA-approved polyethylene specifically certified for safe potable water storage.
What are the exact dimensions of this tank?
The tank measures 39 inches long, 16 inches wide, and 8 inches tall, making it ideal for compact installations.
Will this tank fit my small RV or camper van?
The 386BLANK is designed for smaller RVs and space-limited installations. Measure your existing tank compartment to confirm fitment before ordering.
Is this tank seamless or does it have welded seams?
This is a seamless one-piece rotational molded tank with no welds or joints, providing superior strength and leak-proof reliability.
How much does this tank weigh when filled?
When filled with 21 gallons of water, the total weight will be approximately 175 pounds (21 gallons x 8.34 lbs/gallon plus tank weight).
Can this tank be used for marine applications?
Yes, the FDA-approved polyethylene construction makes this tank suitable for RVs, horse trailers, and marine vessels requiring potable water storage.
Why Buy from Elkhart RV Parts?
- 100% Authentic OEM Parts: We sell only genuine Alpha products - never knockoffs or imitations
- Expert Product Knowledge: Our team knows RV water systems inside and out - use our AI Live Chat for instant assistance
- Fast Shipping: Most orders ship within 1-2 business days
- 30-Day Return Policy: Shop with confidence knowing you're protected
- Authorized Alpha Dealer: Factory-backed quality and support
Upgrade Your RV Fresh Water System Today
Replace your worn-out factory tank with the Alpha 386BLANK - 21 gallons of FDA-approved, leak-proof fresh water storage built to last. Compact design, seamless construction, and authentic OEM quality.
Questions about fitment or installation? Use our AI Live Chat for expert guidance!
| Product type | Fresh Water Tank |
|---|
- What is the capacity of the alpha fresh water tank? The Alpha fresh water tank has a capacity of 21 gallons.
- Is this fresh water tank made from materials safe for drinking water? Yes, the tank is made from premium FDA-approved polyethylene material that is safe for storing drinking water.
- What are the dimensions of this fresh water tank? The tank measures 39 inches in length, 16 inches in width, and 8 inches in height.
- Is this water tank suitable for use in rvs and marine vessels? Yes, this tank is designed to be compatible with RVs, horse trailers, and marine vessels.
- Does the tank have seams or joints that might leak over time? No, the tank features a seamless one-piece construction which provides superior strength and leak-proof reliability.
Factory-Fresh OEM Parts — the same brands installed in new RVs straight from Elkhart. Genuine, name-brand components made to order — never generic, never outdated. Sourced directly from the original RV manufacturers for perfect fit and factory-level quality.

