Hull Pro cleaning guide — underwater hull maintenance
Maintenance Guide

Hull Cleaning & Hull Diver Instructions

Hull Pro is not a set-and-forget coating. How often you clean depends on where you boat and how hard growth is in your area. This guide covers everything a boat owner, hull diver, or certified installer needs to know.

Why It Matters

How Hull Pro Works With Cleaning

Hull Pro is 100% biocide-free. That is one of its strongest qualities, and it is also the reason consistent cleaning is non-negotiable in salt and brackish water. There are no copper compounds or chemicals leaching from the surface to suppress growth. Instead, Hull Pro's smooth, sealed surface makes it significantly harder for fouling to bond. Regular cleaning removes growth before it gets a foothold.

Hull divers are skilled professionals, but a full hull is a large surface and it is easy to miss spots. Those missed areas become problem zones. The solution is frequency, proper tools, and thorough technique — not harder scrubbing after the fact.

No biocides means cleaning drives performance.

Skipping cleanings does not just let growth accumulate. It lets it anchor. Once barnacles establish in areas a diver missed, the job becomes far more difficult, and those spots become persistent magnets for future growth.

Cleaning Schedule by Water Type

How Often to Clean

There is no fixed cleaning schedule that works for every vessel or every season. Cleaning frequency is driven by growth, and growth varies by water type, location, time of year, and how much time the vessel spends in the water. The intervals below are baselines only.

A Note on Saltwater and Brackish Water

Full-time in-water vessels in saltwater or brackish water may need cleaning as often as every 2 weeks during peak growth seasons. We would rather tell you that upfront than have you find out the hard way. Hull Pro still outperforms traditional antifouling paint in ease of cleaning and long-term performance, but it is not a replacement for maintenance. If consistent cleaning at that frequency is not realistic for your situation, Hull Pro may not be the right fit, and we will tell you that before you buy.

Freshwater

End of Season

Baseline

Minimal fouling in most freshwater environments. End-of-season power wash is typically sufficient. Some owners go a full season without cleaning.

Saltwater

Every 2 Weeks

Baseline

Growth-driven. High-fouling seasons may require cleaning every 2 weeks for full-time in-water vessels. Pull and reset every 2–3 months.

Brackish

Every 2–3 Weeks

Baseline

Growth-driven. High-fouling periods can push frequency higher. Pull and reset every 3–4 months for full-time in-water vessels.

Lift / Trailer / Dry-Rack

End of Season

Baseline

Ideal storage. Minimal fouling exposure. End-of-season reset cleaning required before relaunch for warranty coverage.

These are baselines, not guarantees. Your certified installer can help you set a realistic cleaning schedule based on your marina, water type, and local growth season. Getting this right upfront protects your coating, your warranty, and your experience with Hull Pro.

For Hull Divers

Hull Diver Instructions

Hull Pro-coated hulls clean up efficiently with the right technique and tools. The coating is non-sacrificial — you are removing growth from the surface, not removing the coating itself. The steps below apply to every dive.

1

Underwater power washer where available

First pass over the full hull before any pad or scraper work. Blasts soft growth and bio-film efficiently and reduces effort at every step that follows.

2

Full-hull pad-down — 3M white scouring pad

Pad the entire hull surface after the power wash. Do not skip sections. Any area missed becomes an anchor point for growth before the next dive.

3

Extra attention on high-growth zones

Waterline, running strakes, trim tab edges, transom corners, and areas with reduced water flow. Address these on every dive, not just when visible problems develop.

4

Escalate to 3M brown scouring pad

When soft growth has progressed or algae is building, the brown pad provides more abrasion without damaging the Hull Pro surface.

5

Plastic scraper for stubborn hard growth

Low angle, light consistent pressure. Correct escalation when the brown pad is not enough. Never use metal scrapers, wire brushes, or abrasive tools — these can cut through the Hull Pro layer.

6

Document every dive

Photo and video required for warranty in saltwater and brackish water. Log date, conditions, and hull condition at the start of each dive. Any missed cleaning in saltwater voids the warranty.

7

Flag barnacle attachment — recommend haul and reset

Do not force barnacles off underwater. Flag for the boat owner and recommend a haul and reset. Forcing can scar the surface and attract future growth to those spots.

Recommended Equipment

Tools for the Job

Hull Pro does not require aggressive tools. The surface is designed to release growth with minimal effort when cleaned on schedule. The right tools make the process faster and protect the coating from unnecessary wear.

Underwater power washer for hull cleaning

Underwater Power Washer

First choice for divers who have access. Full-hull pass before pad work removes bio-film quickly and makes every subsequent step easier.

3M white scouring pad for hull cleaning

3M White Scouring Pad

Standard tool for routine dive cleanings. Full-hull pad-down on every dive after the power wash pass.

3M brown scouring pad for hull cleaning

3M Brown Scouring Pad

Step up when growth has progressed or algae is building. More aggressive than white, still safe for Hull Pro surfaces.

Plastic scraper for hull cleaning

Plastic Scraper

Escalation tool for hard growth the brown pad cannot remove. Low angle, light pressure. Never substitute metal scrapers or wire tools.

Gas-powered pressure washer for hull reset cleaning

Gas-Powered Pressure Washer (4500 PSI min)

Required for end-of-season and pull-and-reset cleanings. Do not use below minimum PSI — cleaning will be incomplete.

Shark Gel hull acid cleaner

Hull Acid Cleaner / Shark Gel

Hull Pro stands up to all hull acid cleaners and can withstand pure muriatic acid without degradation. We recommend Shark Gel for pull-and-reset cleanings.

See It In Action

Hull Cleaning in the Real World

Hull Pro Reset Cleaning — Haul Out, Scrub, Acid Wash

Watch a full haul-out reset cleaning from start to finish — pressure wash, scrubbing brushes on hard growth, acid wash application, and the final rinse. This is what a proper pull-and-reset looks like on a Hull Pro-coated vessel.

Pier Pressure - Fish River Protection | Orange Beach AL

Pull and Reset Protocol

When and How to Pull and Reset

A pull and reset is a scheduled maintenance step, not a repair. Hull Pro does not wear away with cleaning the way antifouling paint does. The reset process removes accumulated fouling and surface residue and returns the coating to near-original performance without reapplication.

Saltwater: Pull and reset every 2–3 months for full-time in-water vessels.

Brackish: Every 3–4 months. Staying on this interval keeps growth manageable for divers and protects the coating long-term.

Hull Acid Cleaners & Shark Gel

Hull Pro stands up to all standard hull acid cleaners. The coating can withstand even pure muriatic acid without degradation, so you are not limited to a single product. For pull-and-reset cleanings, we recommend Shark Gel — our phosphoric acid cleaner for consistent, controlled results. Wear chemical-resistant gloves and eye protection with any acid cleaner. Do not use on ceramic coatings, natural wood, bare aluminum, or bare uncoated gelcoat.

Reset Checklist

  • Haul the vessel and rinse immediately while the hull is still wet
  • Power wash using a gas-powered 4500 PSI minimum — remove all soft growth and loose fouling
  • Apply hull acid cleaner. Work hard growth with a stiff bristle brush, 3M white pad, or plastic scraper. Allow appropriate dwell time
  • Rinse thoroughly with fresh water until pH neutral
  • Inspect full hull surface — contact certified installer for any touch-up material needed
  • Document with photos and submit to certified installer for warranty records

Hull Pro Diver Reference Guide

Full cleaning protocol, tools, frequency table, and reset checklist formatted for print.

↓ Download PDF Guide

COMMON QUESTIONS

FREQUENTLY ASKED QUESTIONS ABOUT CLEANING

Does Hull Pro eliminate the need for hull cleaning?

No. Hull Pro does not eliminate hull cleaning. In saltwater and brackish water, regular cleaning is required and frequency is driven by growth. What Hull Pro does is make each cleaning faster and easier. Because the surface resists bonding, growth wipes away rather than requiring heavy scraping. The more consistent the schedule, the better the coating performs.

How often do I actually need to clean in saltwater?

It depends on your area and the season. A baseline of every 4 to 6 weeks is a reasonable starting point, but full-time in-water vessels in high-growth areas can need cleaning as often as every 2 weeks during peak seasons. Your certified installer can help you set a realistic schedule based on your marina and local conditions. We would rather tell you this upfront than have it come as a surprise.

Why does my diver need to pad down the full hull every time?

Hull Pro has no biocides, so there is nothing chemically suppressing growth between dives. Any area a diver misses becomes a spot where growth can anchor. Once anchored, that spot is harder to clean and becomes a persistent problem zone. A thorough full-hull pad-down on every dive prevents this entirely.

Can my diver use a metal scraper?

No. Metal scrapers and wire tools can cut through the Hull Pro layer. Always use 3M white or brown scouring pads, or a plastic scraper for hard growth. If growth is too stubborn for these tools, the vessel should be hauled for a pull and reset rather than forced off underwater.

What hull acid cleaners work with Hull Pro?

Hull Pro stands up to all standard hull acid cleaners. The coating can withstand pure muriatic acid without degradation, so you are not limited to a single product. For pull-and-reset cleanings, we recommend Shark Gel, our phosphoric acid cleaner. It is gel formulated to adhere to verticals, making it great for hulls.

What happens if I miss a cleaning in saltwater?

Missing a single scheduled cleaning in saltwater voids the Hull Pro warranty. Beyond the warranty, missed cleanings allow growth to establish and barnacles to attach. The longer between cleanings, the harder the next one becomes. In saltwater, treat each scheduled cleaning as non-negotiable. If you missed a scheduled cleaning, take your boat out, open her up, and contact your diver to get back on schedule.

Does a reset cleaning damage the coating?

No. Hull Pro is non-sacrificial. The acid wash and power wash process removes fouling and surface residue without degrading the epoxy layer. The coating does not wear down with resets. One application is designed to last 5 or more years with proper maintenance.

Find a Certified Installer Near You

Warranty coverage, pull and reset cleanings, and touch-up applications all require a Hull Pro certified installer. Our network covers 100+ locations across the US.

Find a Detailer