The Best Cleaners for Fiberglass Boat

Fiberglass boats are expensive. It is said that a typical fiberglass motorboat costs about $2.50 to 3.00 per lb to build. As it is made of glass, it is essential to clean and maintain it regularly. That is why having the best cleaner is an excellent choice for boat owners.

There are many cleaners available in the market, and in my experience, this wide array of cleaners make it more challenging to choose which one to buy. Thus, here is my review on the best cleaner for fiberglass boats that you can take into account when selecting the most suitable cleaner.

Top 1

STAR BRITE Instant Hull Cleaner

• Easy to use
• Fast-acting formula
• Works better than others

Details

Top 2

MaryKate MK2032 Cleaner

• Convenient to use
• Zero to minimal scrubbing
• Formulated for fiberglass

Details

Top 3

Davis Instruments 790 Cleaner

• Easy to apply
• Comes in gel form
• Specifically formulated

Details

Best Cleaner for Fiberglass Boat Reviews

1. STAR BRITE Instant Hull Cleaner

STAR BRITE is my trusted brand in cleaning and maintaining my boat’s interior and exterior. When I looked for the best fiberglass cleaner, I searched for the STAR BRITE products first and saw this Instant Hull Cleaner. I have high expectations for this cleaner, and it didn’t disappoint.

It is easy to use, and even beginners can utilize it ideally. What I did was transfer the solution into a spray bottle for even coverage. You can also use a sponge if you prefer. Once I’ve coated all the affected areas, I let the solution sit for a few minutes, then rinse it with clean water.

It removes waterline, rust, and other marine stains effortlessly. It is said that this cleaner is a fast-acting formula with mild oxalic acid, and in my experience, I have proven this claim to be valid. My boat looks excellent even without scrubbing. Additionally, you have to wear gloves when using this cleaner to prevent skin irritation.

2. MaryKate MK2032 Cleaner

My brother gave me this MaryKate MK2032 Cleaner because he knew I needed to clean my boat before my birthday. He’s been using this cleaner since 2005, and his boat always received compliments from other people. So, I am confident that it will work well on my boat too.

This cleaner is convenient to use because of its syrup-like consistency. I poured some of the content into a small bucket and used a brush to apply it on my boat. I rinsed the boat with water twice after allowing the solution to rest for 3 minutes. My boat returned to its all-white color after one application, and for that, I can say that it eliminates tough waterline, algae, and rust stains.

Since it is formulated with an instant action solution, it needs zero to minimal scrubbing. In my case, I haven’t cleaned my boat for more than six months, and I only scrubbed some stubborn spots lightly. It is also formulated explicitly for fiberglass, which allows me to work on my boat worry and hassle-free.

3. Davis Instruments 790 Cleaner

I am giving away my twelve-year-old boat, but I wanted it to be in its top shape before I hand it over. So, I looked for a boat fiberglass cleaner that is convenient to use. After some time of searching, I saw this Davis Instruments 790 Cleaner and bought it immediately.

This stain remover comes in gel form, making it easy to apply. The gel sticks well on my boat’s surface, which allows the solution to rest on the impacted area for a long time. I used a paintbrush to apply it on my boat and let it sit for a few minutes. I immediately saw that it instantly works on light stains.

It revives my boat after three applications, and I am happy with its results. This cleaner eliminates tough marine stains without damaging the gel coat. I also like that it is specifically formulated for fiberglass use, allowing me to work freely without any worries.

4. Collinite 920&925 Fiberglass Boat Cleaner

I asked my friend for a fiberglass cleaner for boats, and he recommended this Collinite 920&925 Cleaner. I was skeptical at using this cleaner at first because I’ve never used Collinite products before. Still, I gave it a shot, and it produced outstanding results.

This product comes in a cleaner and wax combo pack. I don’t only get a cleaning solution, but I also receive a finishing wax at a low price. I’m also fond of its easy usage and application. Removing oxidation with its cleaner is easy by hand, but I still have to switch to using a polisher for hard to clean areas. After that, I coated the boat with wax using a soft buffer.

Let’s talk about their performance. I must say that the cleaner removes stains and oxidation with minimal effort. I also like that it doesn’t damage the gel coat like other cleaners I’ve tried before. Moreover, applying the wax afterwards restores my boat’s original condition.

I am happy working with this combo because it doesn’t only clean my boat but also provides protection from outdoor elements. I used the wax thrice to ensure good coverage, and I am satisfied with its shine. I tried it on water and saw that it holds up well.

5. Bio-Kleen M00605 Fiberglass Cleaner

I bought this Bio-Kleen M00605 Cleaner to clean my fiberglass shower bottom and obtained the best results. When I realized that it’s time to clean my boat, I used the excess solution and saw surprising results. So, I purchased another bottle and finished cleaning my boat.

It is simple to use because of its nozzle spray bottle. It comes in a clingy gel form, making it ideal to use on various surfaces. Although it is simple to use, it took me an hour to finish cleaning because of dark and heavy stains. What I did was apply the gel evenly on my boat, let it sit for 5 minutes, then scrub the boat lightly. I washed it with clean water and repeated the steps. This time, I washed the vessel with hot water, and I noticed that it helped achieve faster and better results.

I like this product because it is formulated as a biodegradable cleaner. It allows me to restore my boat’s pleasant appearance and condition with more minor hazards to my health and the environment. Regardless, I still used a mask and protective gear while cleaning my boat.

6. Meguiar’s M6332 Flagship Premium Marine Wax

Meguiar’s is among my trusted brands when it comes to automotive care. That is why I didn’t hesitate to buy this Meguiar’s M6332 Wax when my friend introduced it to me. He knew that I am looking for ways on how to restore shine to fiberglass boats, so he told me about this product.

This premium marine wax is easy to use and apply. However, you need to prepare your boat’s surface before using this product. Ensure that you wash your boat and wipe away any debris on your boat’s surface. Once done with this process, apply the wax with a microfiber cloth, then wipe off any residue after a few minutes. Remember to shake it well before using it.

I like its finished results because it enhances my boat’s overall appearance. When my brother saw my boat, he asked about the product and used it on his boat. However, he told me that he had to apply the wax several times to achieve his desired results.

7. Better Boat Instant Hull Cleaner

My grandfather gave me his ten-year-old boat because he’s migrating to another country next month. The boat is working excellently, but its appearance looks older than my grandfather. I was excited to use it immediately, so I asked my brother to buy me an effective cleaner. He got me this Better Boat Instant Hull Cleaner because he knew that I use other Better Boat products.

This product is created with an instant action formula that helps remove marine stains and build-up quickly. I saw immediate changes upon applying it on my boat. However, I noticed that additional effort and applications are needed for heavy stains. Yes, it works on contact, but you still have to agitate stubborn stains or heavy build-up with a brush to ensure its cleanliness.

What I like most about this product is its simple usage and application. All I did was apply the solution using a spray bottle, let it sit for a few minutes, and then rinse with water. You can also use a sponge for the application. Upon seeing the results, I can say that this cleaner restores a boat’s excellent condition. Even my grandfather approved of its look.

8. 3M 09005 Restorer and Wax

I searched online about how to remove oxidation from fiberglass boats, and the 3M 09005 Restorer and Wax pop out several times on different reviews. Since I always have faith in 3M products, I didn’t have second thoughts of buying it when I came across this cleaner.

I had fun working with this because it is easy to apply. You can choose whether you want it to apply by hand or machine. In my experience, I used an orbital buffer for application and removed the solution with a microfiber cloth. When you are using a device, please remember to spread the product on the area first before activating the equipment. Gradually reduce the speed as you work on it until it begins to dry.

Since it is formulated with a unique solution, a restorer and wax, you can expect your boat to be clean and shiny. It is specially designed to remove heavy oxidation and is safe to use on various boat areas, such as the deck, hull, and gunwale. Using this cleaner annually made me realize that it restores my boat’s best condition and protects it from ultraviolet damage.

9. STAR BRITE 98932 Stain Remover

I have one boat that was left idle for several years outside my vacation house. When I decided to use it, rust and heavy stains welcomed me. I looked for immediate solutions and opted to use DIY cleaners. Several homemade fiberglass boat cleaners later, my boat still looked crappy. So, I went to our local store the following day and asked for recommendations, and this STAR BRITE 98932 Stain Remover, which is specifically engineered for fiberglass use, was on top of their list.

I bought it and went home immediately to try it on my boat, and I was not disappointed. It is easy to use and apply. All you need to do is spray it onto the affected area, let it sit until you see that the stain disappears, and then rinse it off with water. Since it comes in clingy gel form, it sticks onto the surface entirely and penetrates the pigment.

When you apply it, you will see that it dissolves heavy marine and yellow stains. You can also follow it up with light scrubbing to ensure cleanliness. What stood out for me the most is that it has milder acid components than other commercial cleaners. Thus, you can be assured that this product cannot cause significant harm to your health.

10. Bio-Kleen M01609 Hull Cleaner

As I was looking for a fiberglass hull cleaner, I came across this Bio-Kleen M01609 Hull Cleaner. It is an acid cleaner sold in gallons, which I think is more economical than small-sized bottles. Although formulated with acid, it is still designed as a biodegradable cleaner, allowing you to use it comfortably. However, you still need to use protective equipment while using it to avoid serious injuries.

This is convenient to use because it doesn’t need to be diluted. You can directly apply the solution using a rag or sponge. In my experience, I used a spray bottle for even application. I let it dwell for a minute, then rinsed it with water. You can also use a pressure washer if you prefer.

From there, you will see that it removes various marine stains. My boat’s hull was covered with algae stains, and they were wiped off with a single application. Moreover, it needs zero to minimal agitating, even for heavy stains. Last but not least, it is ideal for fiberglass, aluminum, gel coat, and stainless steel use.

11. Meguiar’s M5032 Cleaner Wax

Meguiar’s M5032 Cleaner Wax was recommended by my friend, a professional in marine cleaning and maintenance. Meguiar’s is not a stranger to me, so I bought it and used it immediately. The outcome is fantastic, and I’ve been using it on specific boats since then.

This non-abrasive cleaner is quick to apply and safe to use by hand. Like other Meguiar’s Wax, you have to wash the surface first before applying the cleaner. For application, you can directly apply it on the boat by hand or a polisher. Allow the wax to rest for a minute or two, then wipe it off with a microfiber cloth.

This wax produced a remarkable result as it revives my boat’s color and gives an impressive shine. I also noticed that the polish is more noticeable than before. Another thing I like about this is it eliminates light defects and oxidation. Moreover, it protects my boat from marine elements’ damages. It holds well, even under the harsh sunlight. Thus, I used it twice a year to maintain my boat’s appearance.

12. Simple Green Boat Cleaner for Hulls

I bought the Simple Green Boat Cleaner for Hulls when I saw it online. However, it took me months before I used it because I still have other cleaners available on hand. When I had the opportunity to use it, the results were outstanding, and I wished I used it sooner.

Although it is simple to use and apply, it still needs to be diluted with water before using it. You can choose whether you want it for heavy or medium cleaning. For a more concentrated solution, use a 1:1 ratio. If you wish for a milder one, you can use a 1:10 to 1:30 balance. Once diluted, use a sponge for the application. Ensure that the area is wet before applying it. After that, you can wipe it off with a damp cloth or rinse it with water.

What I like most about this product is its created as an all-purpose biodegradable solution, offering versatility and exceptional results. Additionally, it is safe on various washable surfaces since it is environment-friendly and formulated with mild components.

This product is intended to eliminate grease, grime, and other stains quickly. I am happy that I can degrease my boat even without exerting too much effort. I also noticed that it doesn’t cause abrasion or deterioration even after several uses.

13. Davis 792 Stain Remover

I left my boat soaking for over two months because of community lockdown last year. I was so disappointed to see that my boat’s hull accumulated significant stains during that period. Fortunately, my brother had a stock of his Davis Instruments 792 Stain Remover. I thought this would be like other mediocre gel cleaners in the market, but I was wrong.

What I love most about this cleaner is its economical 2L size. Buying smaller portions of cleaners is usually expensive. So, I prefer having a big-sized solution like this instead. It is easy to apply and wipe off. I used a sponge and rubbed it onto the surface, let it dwell for a few minutes, and then wipe the excess off. I was so amazed that every wipe restores its original color.

I like that it removes rust, waterline, oil, and other stains almost effortlessly. I think it is because it comes in a well-absorbing gel form. You can literally see the difference as soon as the gel is in contact with the affected area. Moreover, it is ideal for fiberglass and white painted surfaces, allowing me to work flawlessly. What’s more interesting is it is formulated as a biodegradable cleaner, which means it doesn’t harm the environment.

14. YachtGUARD Wash and Wax Cleaner

I first learned about YachtGUARD Wash and Wax Cleaner when my colleague posted it on his social media account because he was happy with its performance. I asked him about his experience and became intrigued by its benefits. So, I bought one and tried it on my five-year-old boat.

I like its simple usage and application because I can save time from cleaning and extending my boating time. I mixed 3 ounces of cleaner into a gallon of warm water and applied the mixture to my boat with a sponge. I let it sit for at least 30 seconds and rinsed it thoroughly with clean water. Remember to shake it well before using it.

I am also fond of its concentrated formula with corrosion blocker. It doesn’t only clean my boat but also gives long-lasting protection and shine. Furthermore, it is engineered to be neutral in pH and biodegradable formula, making it environment-friendly. I always want a cleaner that works excellently without causing any degradation on my boat and my surroundings. So, I am happy when I saw this cleaner.

Factors To Consider When Choosing Cleaners For Fiberglass Boat

A fiberglass boat with excessive growth or rigid stains can be challenging to clean. What’s more challenging is to find the most suitable cleaner that will help you finish the job. Hence, I would like to share the factors you can consider when choosing the best cleaners for fiberglass boats.

• Eliminates Tough Marine Stains

Eliminating tough stains from waterline, algae, rust, fish blood, and other marine elements is the primary factor you should consider before purchasing a cleaner. It would be beneficial to ensure that the brand or product you’re choosing has an exceptional reputation for removing light and stubborn stains on a fiberglass boat.

• Ease of Usage and Application

Among the most sought-after factors when choosing cleaners for fiberglass boats is its easy usage and application. Many boat owners prefer cleaners that don’t require extensive labor when cleaning their boats. Fortunately, most ready-made cleaners are easy to use and apply.

• Ingredients or Chemical Composition

Another factor that you should consider is the cleaner’s ingredients or chemical composition. Fiberglass cleaners are primarily formulated with harsh chemicals like hydrochloric acid and phosphate, which may damage your body, boat, and water as well. Thus, as much as possible, choose cleaners with non-toxic or mild compounds to avoid such damages.

• Versatility

Boat cleaning products can be pretty expensive. It is vital to choose a safe cleaner to use on other surfaces apart from fiberglasses, like metal and painted areas. This helps you work without worrying that your boat’s surrounding areas will not deteriorate if they come in contact with the cleaner.

• Fast-acting Formula

The next factor to consider is the product’s fast-acting formula. Boaters need to look for cleaners that offer a quick response time to eliminate tough stains instantly. Moreover, solutions showing instant results allow you to minimize your cleaning time.

• Offers Additional Protection

Fiberglass is a sensitive material that requires delicate care. Therefore, it is beneficial to choose a cleaner that offers additional protection. Fiberglass cleaners with wax or other unique compounds are specifically formulated to ensure that your vessel can maintain its appearance after cleaning.

• Price

Some boat owners consider the product’s price above anything else. However, if you look at its pricing first without carefully scanning the factors above, you are more likely to make a wrong decision. The cleaner’s effectiveness does not depend on its price, but it would be helpful to consider pricing based on the factors mentioned above.

The Different Types of Cleaners for Fiberglass Boat

There are many types of cleaners for fiberglass boats available today, making it easy for boat owners to maintain their vessels in excellent condition. Each class offers distinctive benefits and disadvantages. So, always use them at your own risk.

• Commercial Cleaners

The most convenient and popular type of cleaners for fiberglass boats is the commercial type. It is a ready-made formula that you can find at your local marine shops or online stores. However, such cleaners can be quite expensive.

Common types of commercial cleaners:

• Gel

Beginners commonly use gel cleaners as they are easy to use. All you need to do is apply it to your boat and let it do its job. Some experienced boaters also use gel cleaners when they want to save time cleaning their boats.

• Liquid

Another type of commercial cleaners is the liquid form. Liquid cleaners are chosen mainly by boat owners who want delicate cleaning because they offer broad coverage areas.

• Homemade or DIY Cleaners

Many boat owners opt to use homemade cleaners because the ingredients are readily available at home. However, others don’t recommend these cleaners because of different risks or dangers, especially for beginners. Thus, take extra care and always seek advice from experts when you want to use DIY cleaners.

Some homemade cleaners are as follows:

• A mixture of water, isopropyl alcohol, and ammonia
• A mix of cornstarch, warm water, vinegar, and ammonia
• A mixture of baking soda, warm water, vinegar, and ammonia
• Baking soda paste (baking soda and water)
• A combination of water and vinegar

Other boaters use muriatic acid for cleaning, but it is not advisable for non-professionals because it is hazardous.

Benefits and Drawbacks of Using Cleaners for Fiberglass Boat

In this section, I will share with you the general benefits and drawbacks you may experience in using cleaners for fiberglass boats. Let me discuss the advantages first.

• Removes Stubborn Stains

The primary benefit of using cleaners for fiberglass boats is their ability to remove stubborn stains, which water and soap cannot eliminate. Each cleaner contains a specialized formula that helps you clean your boat successfully.

• Saves Time and Effort

Most cleaners are easy to use and apply, allowing boaters to save time and effort. You can save yourself from scrubbing your boat for extended periods when you use cleaners, as they are engineered with a powerful formula that lifts off stains quickly. That is why it is essential to look for cleaners offering instant action.

• Prolong Your Boat’s Life Span

Marine elements, such as waterline stains, oxidation, algae stains, can degrade your boat over time. So, cleaning your boat regularly is crucial for every boat owner to restore its original condition. However, ensure that you are using an effective cleaner, as much as possible with extra protection, to help prolong your boat’s life span.

Now that you know the benefits of using cleaners for fiberglass boats, it is time to summon the drawbacks that you may experience. Knowing these disadvantages beforehand will help you make the right decisions and take precautions when using cleaners.

• Costly

The most common drawback of using cleaners is its additional cost. Some cleaners are expensive, and they usually come in small portions. Moreover, many boat owners had to try different cleaners before having the most suitable cleaners for their boats. This action is costly, so try to look for reviews first before purchasing cleaners.

• Surface Damage

Cleaners are generally formulated with harmful and toxic chemicals that may deteriorate or damage your boat’s surface. Some cleaners are intended for fiberglass only, while others are ideal for various surfaces, including painted bottom and metal. It is possible to leave a scratch when cleaning fiberglass boats quickly. That is why you have to do it carefully and as much as possible, use mild cleaners only.

• Health Issues

As cleaners contain harmful substances, health issues may be an issue when using cleaners. Thus, clean your boat in a well-ventilated area while wearing protective equipment to avoid health damages like skin or eye irritation and respiratory problems.

How Do I Remove Stains From My Fiberglass Boat

Removing stains from a fiberglass boat is made easy with available cleaners today. All you need to do is apply your desired solution onto your boat and let it sit for a few minutes before rinsing thoroughly. You can use commercial cleaners like the products listed above or handmade cleaners for removing stains from your boat.

How To Clean a Fiberglass Boat Deck

It takes time and effort to ensure your deck’s cleanliness, but when you have the right cleaner for boat deck and complete equipment, you can minimize your overall cleaning time. Let me show you how.

• Using a cloth or rag, wipe away dirt or debris on your deck before washing it with water.
• After washing your deck with water, let it dry naturally before starting the actual process.
• Once the deck is dry, apply the cleaner on your deck. Make sure to spray or put it on all areas evenly.
• Let the cleaner sit for at least three minutes.
• Start scrubbing your deck with a brush gently to avoid damages.
• After rubbing, rinse your deck with clean water to remove the remaining debris.
• If there are areas that still have some stains, repeat steps 4-7 until your entire deck becomes clean.
• Once cleaned, coat your deck with a polisher to provide protection and shine to your boat. This step is optional, but it will give you the best results.

Is It OK To Use Bleach On A Fiberglass Boat

Although bleach is an excellent cleaner alternative, it is still not advisable to use it on fiberglass boats. Yes, you can use bleach on a fiberglass boat, but it will damage your boat when you use bleach continuously.

Conclusion

Removing stains from a fiberglass boat is only one clean away when you have suitable cleaners on hand. However, the cleaner selection process may be confusing, mainly because of the various brands today. Plus, you have to consider different factors and be mindful of the product’s benefits and drawbacks before purchasing a cleaner.

Hopefully, this review of the best cleaner for fiberglass boats came in handy when you doubt your decision in choosing the right cleaner.

James Harvey

“I am James Harvey – founder of Boating Basics Online. It is established with the drive to help out first-time boaters, which are those desiring to explore their way through the water. So if you are new to boating, start from here with me. “