Cleaning Aluminum Boats: Removing Algae The Right Way

Algae can be a stubborn and unsightly problem for boats, and it's important to know how to clean it off effectively without damaging the hull. While there are many methods, some of the most popular include using bleach, commercial products like Algex, or muriatic acid. Each method has its own advantages and considerations, such as the level of elbow grease required, potential damage to the boat, and environmental impact.

How to clean algae off an aluminum boat

Use Algex to remove algae without damaging the aluminium

Algex is a great product to use to remove algae from your aluminium boat without causing any damage. It is an acid-based product that contains several acids in different proportions, plus inhibitors and other ingredients. It is as tough as you can get without damaging the aluminium.

To use Algex, start by spraying it onto the algae. Keep the surface wet and let the product work for about 20 to 30 minutes. Then, give it a scrub with a stiff brush and either hose it off or use a pressure washer. If the algae are particularly stubborn, you may need to repeat the process several times.

Algex is also safe to use on other parts of your boat. You can apply it to the painted motor bracket and lower leg of the outboard without causing any damage. It will not pit aluminium or strip paint. It will, however, remove rust and oxidation, leaving your boat as good as new.

In addition to Algex, there are a few other products you can use to get your boat looking its best. If, after removing the algae, your aluminium is stained, you can use Alumabrite CBX to brighten it. You can also apply Alumetron to protect the finish and VS721 to reduce the attachment of algae and Zebra Mussels, making future clean-up easier.

Bleach can kill algae, but it can also damage eyes and skin

Bleach is a corrosive substance that can be used to kill algae on boats. However, it is essential to exercise extreme caution when using bleach as it can cause serious damage to the eyes and skin.

When using bleach, it is crucial to wear protective gear, including rubber gloves and goggles, to safeguard your eyes and hands from splashes and direct contact. Working in a well-ventilated area or outdoors is also recommended, as the strong chlorine odour and fumes released by bleach can irritate the nose, throat, and lungs, especially for individuals with asthma.

If bleach comes into contact with your skin, immediately remove any contaminated clothing and jewellery. Then, rinse the exposed area with plain water for at least 10 minutes to dilute and remove the bleach. After rinsing, gently wash the skin with mild soap and water. Keep in mind that bleach weakens the skin's natural barrier, making it more susceptible to burning and tearing.

The effects of bleach on the skin depend on the concentration, duration of exposure, and the amount of bleach that comes into contact with it. A minor bleach burn may heal within a few days, but a severe burn may take weeks or even months to recover. Bleach can also cause allergic reactions on the skin, leading to painful red welts.

In the event of bleach entering your eyes, it is crucial to act promptly. Rinse your eyes with lukewarm water immediately for at least 10 minutes. During this process, remove any contact lenses and dispose of them. After rinsing, seek emergency medical treatment to ensure there is no lasting damage to your eyes. Bleach can cause permanent harm to the nerves and tissues in your eyes, and it may take up to 24 hours to determine the full extent of the damage.

To summarise, while bleach can be effective in killing algae, it is crucial to prioritise safety and handle it with caution. Always wear protective gear, work in well-ventilated spaces, and be prepared to take swift action in case of skin or eye contact.

Use a pressure washer to clean algae off

To clean algae off an aluminum boat using a pressure washer, there are a few key steps to follow. Firstly, it is important to prepare the boat by removing any loose equipment, such as seat cushions, canopies, and other removable items. Close all sliding doors, windows, hatches, and portholes to prevent water from entering the boat's interior. Cover fragile areas, including electronics, vents, and exhausts, to protect them from water damage.

When using the pressure washer, it is recommended to start from the top of the boat and work your way down. This prevents dirt and debris from settling on already cleaned areas. Maintain a consistent distance of 1 to 2 feet between the pressure washer nozzle and the boat's surface to ensure effective cleaning without causing damage. Use nozzle attachments that provide a wide spray pattern for general cleaning and a narrow spray pattern for targeting tough stains and crevices.

While pressure washing, it is important to wear adequate protective gear, such as goggles and gloves, to shield yourself from debris and high-pressure water. Be mindful of your surroundings and always direct the nozzle away from yourself and others. After pressure washing, thoroughly rinse the boat with clean water to remove any remaining detergent or debris.

For heavily soiled areas, you can use a scrub brush attachment with your pressure washer. Apply a detergent or an algae removal product, such as Algex, and let it sit for 20 to 30 minutes before scrubbing and rinsing. If the algae are particularly stubborn, you may need to repeat this process several times.

Apply a protective coating like Alumetron to make it harder for algae to stick

To prevent algae from sticking to your aluminum boat, you can apply a protective coating like Alumetron. Alumetron is a clear polymer coating that bonds chemically and mechanically to aluminum. It protects aluminum from oxidation, tarnish, UV, corrosion, salt spray, road film, and acid rain. It is also environmentally safe and non-flammable.

Step 1: Clean the Boat

First, ensure your boat is clean and dry. If your boat is new, simply clean and degrease the aluminum. If there is fouling, use a product like Algex to remove it. For tarnished aluminum, use a product like Alumabrite CBX to remove oxidation and stains.

Step 2: Prepare the Surface

Make sure the surface of your boat is wet. Then, spray Boat Clean Plus onto the surface and wash it with a marine power mitt, cloth, sponge, or pressure washer. Rinse and dry the boat.

Step 3: Apply Alumetron

Alumetron is applied by wiping it onto the surface with a lint-free cloth pad. Fold the cloth into a pad about 6 inches long. Dip the folded edge of the pad into Alumetron and squeeze out any excess. Apply Alumetron in long, smooth, wet-on-wet, overlapping strokes, always wiping with the grain. Apply a total of four thin coats, allowing each coat to dry before applying the next.

Step 4: Cure and Protect

Allow the Alumetron to cure for 48 hours. Then, to protect surfaces that will be continuously submerged in water, apply 2 coats of VS721 Bottom Coat below the waterline. This will make cleaning and maintenance easier and increase the longevity of your boat.

By following these steps, you can effectively apply a protective coating like Alumetron to your aluminum boat, making it harder for algae to stick and keeping your boat looking shiny and new.

Clean algae off as soon as the boat leaves the water

To clean algae off an aluminium boat as soon as it leaves the water, it is recommended to use a pressure washer. If there is tough, dried-on algae, you can use a product like Algex, which is an acid-based spray. Spray it on, leave it for 20-30 minutes, scrub with a stiff brush, and then hose or pressure wash it off.

If you want to use a bleach solution, you must dry dock your boat away from lakes or rivers, as bleach can be harmful to the ecosystem. Make sure the area is well-ventilated, and wear protective clothing, including gloves and goggles. First, scrape away any large clumps of algae or caked-on grime with a putty knife. Then, wipe down the entire boat with water. Next, mix a bleach solution with warm water in a 4:1 ratio, and use a nylon brush to scrub the hull in a circular motion, removing any algae buildup. Finally, rinse the hull with water to remove any bleach solution.

If you are unable to use a pressure washer or acid-based product, there are other methods you can try. One option is to use a brush to remove the algae while the boat is still in the water. You can also try using a garden hose on its highest setting to wash off the algae. Additionally, some people recommend using toilet cleaner or muriatic acid to remove algae, but be sure to wear protective gear when handling these harsh chemicals.

To reduce the amount of cleaning required in the future, you can apply a protective coating to your boat. One option is to use a product like Alumetron, which fills in the grains of the aluminium, making it smoother and reducing the ability of algae to stick. You can also apply a bottom coat like VS721, which will help reduce the attachment of algae and make cleanup easier.

Frequently asked questions