Aluminum Chlorohydrate Storage — ACH Coagulant Tank Selection
Storing Aluminum Chlorohydrate (ACH)? Start Here
ACH is a water-treatment coagulant — a mildly acidic aluminum solution that's gentler than alum and a clean fit for a poly tank. It's the standard coagulant for low-alkalinity source water because it doesn't crash the pH the way alum can.
Can you store it in a poly tank? Yes — the standard.
ACH (pH ~3.8–4.5, with chloride) stores in HDPE rotomolded tanks with PVC/CPVC piping, EPDM gaskets, and PP fittings — 1,500–15,000-gallon bulk tanks are typical at municipal water plants. Keep metal off wetted parts (the chloride pits stainless). For drinking water, use NSF-60 product and an NSF-61 tank.
The safety that actually matters
- Mildly acidic — standard acid PPE, vented tank, 110% containment.
- Non-metallic wetted parts (PVC/CPVC/poly) to avoid chloride corrosion.
Common questions
- Poly OK for ACH?
- Yes — HDPE with PVC/CPVC piping and EPDM gaskets is the municipal standard.
- ACH or alum?
- ACH consumes less alkalinity per dose, so it's preferred for low-alkalinity water where alum would crash the pH.
Aluminum Chlorohydrate storage tanks from OneSource
For aluminum chlorohydrate storage, specify either HDPE or crosslinked polyethylene (XLPE) rated to specific gravity 1.9. Verified, compatibility-matched options:
- Snyder Industries 22 Gallon ASTM XLPE Black Heavy Duty Vertical Storage Tank (1.9 SG)
- Snyder Industries 150 Gallon XLPE Chemical Feed Station Tank (1.9 SG)
- Snyder Industries 500 Gallon ASTM XLPE Black Double Wall Tank (1.9 SG)
- Snyder Industries 1500 Gallon 45 Degree XLPE Cone Bottom Tank in White (1.9 SG)
- Snyder Industries 5000 Gallon XLPE Vertical Liquid Storage Tank with ASTM Certification (1.9 SG)
Confirm chemical compatibility and a ZIP freight quote with our team at 866-418-1777.
Designing the storage system, not just picking a tank?
Vendor-neutral engineering guides from our custom fabrication team - material of construction, containment, and code, matched to your chemistry.
Explore: FRP & Fiberglass Tanks · Double Wall Tanks · Solvent Recovery · Custom Fabrication Hub
Sources & References
All compatibility ratings, hazard classifications, and chemical identifiers on this page are sourced from authoritative third-party publications. Verify against the original references before final specification.
- PubChem Compound Database — entry for Aluminum Chlorohydrate (CID 71586946, CAS 12359-72-7). pubchem.ncbi.nlm.nih.gov. National Library of Medicine / NCBI. Canonical chemical-identity reference.
- Snyder Industries Chemical Resistance Recommendations — system-of-construction guidance for polyethylene chemical-storage tanks at industrial ASTM 1.9 SG design rating. SNY-3041 Chemical Resistance Chart. Snyder Industries, current edition. Resin + fitting + gasket + bolt MOC matrix.
- Equistar Technical Tip — Chemical Resistance of Polyethylene — LDPE / MDPE / HDPE rating chart by concentration and temperature, distributed by Enduraplas. enduraplas.com (PDF). Equistar polyethylene resin chemical-resistance data, distributed via Enduraplas.
- NFPA 704: Standard System for the Identification of the Hazards of Materials for Emergency Response. nfpa.org. NFPA 704 'fire diamond' health/flammability/instability/special-hazard rating system (0–4 scale).
- UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS), current revision. unece.org/transport/ghs. GHS pictograms, signal words, and H-statement codes referenced in this guide.
- ASTM D1998 — Standard Specification for Polyethylene Upright Storage Tanks, current edition. astm.org. Cited as the design-specific-gravity standard (typically 1.9 SG) for industrial chemical-service polyethylene tanks.
- NIOSH Pocket Guide to Chemical Hazards — occupational exposure limits, PPE, and IDLH data for Aluminum Chlorohydrate. cdc.gov/niosh/npg. CDC / NIOSH chemical-specific occupational-safety reference.