MA5X Barnacle Remover - Marine Hull & System Cleaner

Barnacle Off - Concentrated Marine Growth Remover

Barnacle Off breaks down barnacles, sea lime, rust, salt deposits, and organic buildup on contact, no mechanical scraping needed. The concentrated phosphoric acid formula works fast on boat hulls, waterlines, and seawater cooling systems, clearing the buildup that causes overheating, flow restriction, and impeller damage before it becomes a repair bill.

How to Use

Pre-rinse to remove loose growth, then apply diluted with clean water using an acid-resistant sprayer or brush. For heavy fouling, dilute 1:4 (one part concentrate to four parts water). For routine maintenance, 1:10 works well. Let it dwell up to 10 minutes, agitate if needed, then rinse thoroughly with fresh water. Apply on cool surfaces out of direct sun for best results.

For seawater cooling systems and heat exchangers, circulate diluted product through the circuit in a closed loop, then flush completely with fresh water.

What It Works On

Formulated for fiberglass, gelcoat, painted hulls, and seawater cooling components when used as directed. Effective on boat hulls, waterlines, marine trailers, and engines with saltwater or mineral scale buildup.

Safe Handling - Required Before Use

Signal word: DANGER. This product causes serious eye damage and skin irritation on contact. Wear chemical-resistant gloves and eye protection whenever handling concentrate. Avoid breathing mist or spray. Keep out of reach of children. If eye contact occurs, rinse with water for at least 15 minutes and seek medical attention immediately. Store away from alkalis and reactive metals.

This is a phosphoric acid solution (pH 1–2). It is non-flammable and biodegradable. View the full Safety Data Sheet (SDS).

Made in the USA. Available in 32 oz and 1 gallon.

Marine service businesses and boatyards cleaning multiple vessels can order Barnacle Off in a 55-gallon drum through our Bulk & Wholesale collection.