Calcium Ammonium Nitrate (CAN-17, 17-0-0) Storage & Tank Compatibility

Storing Calcium Ammonium Nitrate (CAN-17, 17-0-0)? Start Here

Calcium Ammonium Nitrate solution — sold as CAN-17 (17-0-0) — is a clear, water-thin liquid fertilizer that supplies both nitrate and ammoniacal nitrogen plus soluble calcium in a single product. It is a blend of dissolved calcium nitrate and ammonium nitrate, often described by the double-salt formula 5Ca(NO₃)₂·NH₄NO₃·10H₂O, carried in water at roughly 1.5 specific gravity. Growers value it because the nitrate fraction is immediately plant-available while the ammoniacal fraction feeds longer, and the calcium supports soil structure and crop quality.

It is applied directly to soil, banded/injected, or run through fertigation systems. Material of construction matters because the solution is dense and corrosive to bare and galvanized steel, even though it is non-flammable and only a mild irritant. Choosing the right tank resin and excluding incompatible metals protects both the equipment and the integrity of the fertilizer.

Polyethylene (HDPE / XLPE) Compatibility — Verdict: Suitable

Polyethylene is a compatible, recommended material for CAN-17. Published resistance data rate aqueous ammonium nitrate at any concentration and calcium nitrate at 50% as satisfactory in HDPE at both 70°F and 140°F, and polyethylene does not corrode or scale in nitrate salt service. The near-neutral pH (~6) and aqueous, non-oxidizing-classified nature of the dilute solution keep it well within poly's comfort zone.

The one design caveat is weight, not chemistry: CAN-17 runs around 1.5 specific gravity, so always specify a tank rated for at least 1.5 SG (a high-density / heavy-duty poly rating) rather than a standard 1.0-1.35 SG water tank. Use compatible fittings and gaskets (EPDM/Viton), and keep CAN-17 segregated from urea-ammonium-nitrate (UAN) lines — mixing CAN with UAN or other calcium-nitrate solutions throws a milky precipitate that plugs nozzles.

Material compatibility at a glance

CAN-17 is a dense aqueous double-salt solution with near-neutral pH and no flammability, so polyethylene (HDPE/XLPE) is the workhorse material of construction — just size the resin for the ~1.5 specific gravity. Avoid bare steel, galvanized, and zinc, which nitrate solutions corrode.

Ratings: S suitable · C conditional / limited · U unsuitable. Verify against the cited resistance charts and your concentration/temperature before specifying.

The safety that actually matters

• Harmful if swallowed (H302); high nitrate intake can cause methemoglobinemia — headache, fatigue, blue lips/skin.
• Causes skin irritation (H315) and serious eye irritation (H319) — wear chemical goggles and gloves.
• Non-flammable as supplied, but on heating/fire it decomposes to release oxides of nitrogen and ammonia — toxic fumes.
• Calcium-containing CAN solution is not classified as a DOT oxidizer (unlike solid ammonium nitrate), but keep away from combustibles, acids, and reducing agents.
• Harmful to fish and aquatic organisms — contain spills; prevent entry to drains and waterways.
• Do not co-mingle with UAN or other calcium-nitrate streams (precipitate); always confirm the supplier SDS for the specific grade.

Common questions

Can I store CAN-17 in a poly (HDPE/XLPE) tank?

Yes. Polyethylene is compatible with aqueous calcium ammonium nitrate solution. Because CAN-17 is dense (~1.5 specific gravity), choose a tank rated for at least 1.5 SG rather than a standard water tank, and use compatible fittings and gaskets.

Is CAN-17 an oxidizer or explosive like solid ammonium nitrate?

No. The dilute, calcium-containing solution is not classified as a DOT oxidizer the way solid ammonium nitrate is. It is non-flammable as supplied. It can still release nitrogen oxides and ammonia if heated in a fire, so keep it away from combustibles and acids.

What is the pH and density of CAN-17?

Representative product data show a near-neutral pH of about 6-6.5 and a specific gravity around 1.5 (roughly 12.7 lb per US gallon). Values are SDS-dependent — confirm against your supplier's data sheet.

Why can't I mix CAN-17 with UAN in the same tank?

Combining calcium ammonium nitrate (or any calcium-nitrate solution) with urea-ammonium-nitrate forms a thick, milky-white insoluble precipitate that plugs nozzles and lines. Keep the two products in separate, dedicated storage and feed systems.