CRC Hull & Bottom Cleaner for Fiberglass Boats 32oz — Fast-Acting Waterline, Algae & Rust Stain Remover Safe for Gel Coat

CRC Hull & Bottom Cleaner 32oz is a fast-acting fiberglass cleaner formulated to lift waterline, algae, rust and exhaust stains without damaging gel coat.

Designed for boat owners and marine maintenance pros, this concentrated 32-ounce formula targets the common tough discolorations that build up on fiberglass hulls. It works quickly on visible stains along the waterline and other areas affected by algae, barnacle residue, rust, and fuel or exhaust marks. Safe for gel-coated surfaces when used as directed, the cleaner helps restore a uniform finish so you can preserve your vessel's appearance between detailing sessions.

How quickly will I see results on waterline stains?

Most waterline and algae stains begin to loosen and fade within minutes of application, especially when allowed to dwell on the spot. Heavier or older staining may require a short second pass or gentle agitation with a soft brush to fully remove embedded discoloration.

• Works rapidly on fresh and moderate stains
• Heavier stains: repeat application or light brushing
• Visible improvement often within minutes

Can I use this on any part of my boat's exterior?

Use this cleaner only on fiberglass surfaces with gel coat; it is formulated specifically for those finishes. Avoid applying on painted, metal, or non-gelcoat plastics where ingredients could alter the surface.

• Safe for gel-coated fiberglass hulls when used according to instructions
• Not recommended for painted or non-gelcoat surfaces
• Avoid prolonged contact on trims, chrome, or aluminum

What is the correct way to apply CRC Hull & Bottom Cleaner?

Apply the cleaner to the stained area, allow it to sit briefly to break down deposits, then rinse or wipe away. For stubborn marks, use a soft nylon brush or cloth to work the product gently and then rinse thoroughly to prevent residue.

• Apply directly to stain; let dwell a few minutes
• Gently agitate with soft brush for persistent spots
• Rinse completely after cleaning to remove residues

Does this product affect gel coat or require special care after use?

Formulated to be safe on gel coat when used properly, the cleaner should not harm the finish. After treatment, rinsing and optional waxing or polishing will help protect the area and restore gloss.

• Safe for gel-coated surfaces when following directions
• Rinse well and dry before applying protectants
• Use protective gloves and avoid eye contact during use

Who is this for: CRC Hull & Bottom Cleaner 32oz is aimed at boat owners, marina staff, and detailers who need a reliable solution for removing common marine stains from gel-coated fiberglass. If you maintain pleasure craft, run rental fleets, or perform seasonal boat prep, this compact bottle gives a strong, targeted cleaner to tackle waterline, algae, barnacle residue, rust, and exhaust marks between full restorations.