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We wanted to find out which was the best hull cleaner to remove stains and tough buildups on a boat hull. We actually purchased the hull cleaners and tested each one. The test subject was a boat that was used in the water for a season without being cleaned between uses. With each cleaner having some similarities as well as some differences, we wrote a bit about each one. Bellow you will find the additional details on the products we used.
Why is it Important to Keep your Hull Clean?
Having your boat in the water will more than likely mean it will start to accumulate some marine buildup. Typically algae, salt, and other pollutants tend to foul the bottom of your boat up especially if you leave it in for any extended period of time. Cleaning this buildup off your hull can be a tough job but it’s one you want to make sure you do.
If left untreated, these nasty elements could eat away at and damage your boats fiberglass and gel coat. This isn’t something anyone wants for their boat. The gel coat on your boats hull protects the fiberglass and keeps a nice smooth surface. If the gel coat is damaged, the fiberglass will be exposed and will begin to slowly break down. This can be a very extensive repair if left untreated.
On top of damage being done to the fiberglass hull, the smooth gelcoat also keeps resistance down between the water and your boats hull. This will ensure you have the best fuel mileage, top speed, and ease of getting up on plane. Even with a gel coat in good condition, leaving a hull uncleaned means a buildup that will also affect the resistance with the water as the hull will be carrying extra debris. Finding the best hull cleaner for your use will help keep your boats hull clean with minimal resistance.
Our Test Results and Product Ranks from 1-10
Below, you’ll find the outcomes of our hull cleaner test, our recommended hull cleaner, and pros and cons of hull cleaners used during our test. We were very impressed with a lot of the products and had a tough time ranking each one. Check below to see how we ended up ranking each product as well as some details on why we ranked each one the way we did. Hopefully you’ll find out which is the best hull cleaner for you!
1. Marykate On & Off Hull & Bottom Cleaner
Marykate On & Off Hull & Bottom Cleaner is one of the most well known hull cleaners on the market. Its extremely powerful acid-based solution will fight the toughest stains and marine buildup on your boats hull. It works instantly as soon as it’s applied. For standard staining and discoloration, just simply wipe or spray it on, then spray it off with a hose. If there is a significant amount of buildup a light scrub may be required but On & Off will be sure to do most of the work.
Pros:
- Works instantly to remove scum buildup and stains
- Biodegradable formula
- Simply brush on and spray off, no scrubbing required for standard discoloration, light scrubbing may be required for heavier applications or older stains
Cons:
- Acid-based solution can be harsh on other surfaces such as metal trailers
- Strong odor, recommended use in a ventilated area and or used with a mask
- Recommended use of gloves and eye protection
- Does not come with a spray nozzle
Our overall impression of Marykate On & Off Hull & bottom cleaner is this is one impressive cleaner. As advertised, it started working instantly and took the stains and discoloration off our test boat as soon as it was applied. If using it, care should be taken to protect your skin, eyes, and lungs. Care should also be taken when using it around your boat trailer to protect the paint and metals. Overall, On & Off is one of the best hull cleaners if you have a tough job to tackle with a severely fouled hull!
2. Zing Professional Boat Hull Cleaner
Zing Professional Boat Hull Cleaner is another high strength commercial grade cleaner used by marinas and boaters. Zing is an acid based cleaner that not only removes scum and other buildup, but also loosens mussels and barnacles that are attached to hulls.
Zing Professional Boat Hull Cleaner comes in a variety of sizes to accommodate your needs. Whether your are a hobbyist trying to maintain your own boat, or a business owner maintaining the pride and joy of many boat owners, This could be the best hull cleaner for you as there is a perfect size. Below you can find some of the key features.
Container Size:
- 32 ounces
- 1 gallon
- 5 gallon
- 55 gallon
Pros:
- Commercial high strength
- Removes mussels and barnacles attached to hulls
- Works instantly to remove scum buildup and stains
Cons:
- Acid-based solution can be harsh on other surfaces such as metal trailers
- Strong odor, recommended use in a ventilated area and or used with a mask
- Recommended use of gloves and eye protection
- Does not come with a spray nozzle
Our overall impression of Zing Professional Boat Hull cleaner was a top of the line product. As advertised, it started working instantly and took the stains and discoloration off our test boat as soon as it was applied. If using it, care should be taken to protect your skin, eyes, and lungs. Care should also be taken when using it around your boat trailer to protect the paint and metals. After using the product and comparing it to the others, we agree that it is also one of the best hull cleaners if you have a tough job to tackle with a severely fouled hull!
3. Better Boat Instant Hull Cleaner
Better Boat’s Instant Hull Cleaner is another tough and powerful hull cleaner that will be sure to leave your hull sparkling clean and can be ranked with some of the best hull cleaners around. Similar to the other high strength cleaners, Instant Hull Cleaner works instantly upon application. In most scenarios, this cleaner can be simply sprayed or wiped on, with a simple fresh water rinse afterward. We weren’t disappointed after using this product and its definitely proven to work on some of the toughest buildup.
Container Size:
- 32 ounces
Pros:
- Removes scum and stains instantly
- Simply brush on and spray off, no scrubbing required for standard discoloration, light scrubbing may be required for heavier applications or older stains
- .Can be used on fiberglass and painted hulls
- 30 day money back guarantee
Cons:
- Best if used with gloves, safety glasses, and good ventilation
- Strong odor
- Can potentially etch concrete and damage metals it comes in contact with if not immediately rinsed
- Does not come with a spray nozzle
Instant Hull Cleaner was another one of the best hull cleaners for heavy duty jobs. Similar to some of the others, it started working instantly and took the stains and discoloration off our test boat as soon as it was applied. Like the other potent cleaners, care should be taken to protect your skin, eyes, and lungs. Care should also be taken when using it around your boat trailer to protect the paint and metals. One of the additional items we liked about Instant Hull Cleaner is Better Boat stands by their product and offers a 30 day money back guarantee if not satisfied. We were extremely impressed and won’t be returning our bottle!
4. Star brite Instant Hull Cleaner
Another classic line of hull cleaners is Star brites Instant Hull Cleaner. This hull cleaner is a popular brand that you’ll typically find in most stores or online shops that deal with boats and marine cleaning supplies. Instant Hull Cleaner is quick to remove even the toughest stains on your boats hull. Star brite Instant Hull Cleaner comes in two different sizes to accommodate the size of your fleet. Whether your are a hobbyist trying to maintain your own boat, or a business owner cleaning many boats, you get the pick of whether you will need more or less. Here are the different sizes you can find this hull cleaner in:
Container Size:
- 32 ounces
- 1 gallon
Pros:
- Works instantly on rust, stains, and scum
- Can be used on fiberglass, metal, and painted surfaces
- Simply brush on and spray off, no scrubbing required for standard discoloration, light scrubbing may be required for heavier applications or older stains
Cons:
- Recommended use with gloves
- Does not come with spray nozzle
Application Instructions:
- Shake well
- Apply using a spray mechanism, sponge, or rag
- Let cleaner remain on surface for at least 2 minutes
- Rinse with water
- Extra dirty or stained surfaces may require a second application
Starbrite Instant Hull Cleaner can be applied by either spraying or with the use of a sponge. The bottle does not come with a spray nozzle so a separate sprayer or spray bottle will need to be purchased if that’s the route you wish to take. One of the things we liked about this cleaner is even though it does an excellent job, it’s not as powerful, and dangerous, as some of the more potent commercial cleaners. If your boats hull is discolored but not in an extreme way, Instant Hull Cleaner might be the best hull cleaner for you as still gets the job done without being over the top with chemicals.
5. Star brite Instant Hull Cleaner Gel Formula
Star brite makes a gel version of their Instant Hull Cleaner that has a lot of the same top notch attributes as the original. Similar to the original Instant Hull Cleaner, this is a popular product that you’ll typically find in most stores or online shops that deal with boats and marine cleaning supplies. Instant Hull Cleaner is quick to remove even the toughest stains on your boats hull.
Container Size:
- 32 Ounces
Pros:
- Gel formula sticks to the hull instead of running off, especially on the underside and extreme angles
- Spray bottle included
- Fumes and chemicals are less harsh although still present
- Less harsh on trailers and metals than other brands
- Removes scum instantly
- No/light scrubbing required
Cons:
- Recommended use with gloves
- Spray bottle is not very heavy duty
- Spray bottle takes more time for a large hull than a larger sprayer
One of the greatest things we found that put Star brites Gel Formula in the running for best hull cleaner was the thicker consistency of the product. This helped the product stay on the hull for longer, which meant longer cleaning time. The less viscus cleaners have a tendency to run off the hull easily where as the gel formula moved slower with its thick consistency. Along with the great clinging characteristics of the gel, this version of Instant Hull Cleaner had all of the same cleaning power as the original. On top of all that, it even comes in a bottle with a spray nozzle for quick and easy use right off the store shelf!
6. Star brite Sea Safe Hull Cleaner
As avid boaters, one of the greatest assets we have is the water we enjoy. We know it’s our responsibility to not only enjoy but help protect the seas we use on a regular basis. If you’re looking for the best hull cleaner to not only do a great job cleaning the bottom of your boat but is also eco friendly and safe for the environment, look no further than Star brites Sea Safe Hull Cleaner. This cleaner does everything the other Star brite hull cleaners are capable of, except on a level that’s not only safer for the environment, but safer for the end user as well.
Container Size:
- 32 ounces
Pros:
- Works instantly on rust, stains, and scum
- Biodegradable, environmentally friendly
- Simply brush on and spray off, no scrubbing required for standard discoloration, light scrubbing may be required for heavier applications or older stains
- Does not contain harsh acids, safer than most heavy duty hull cleaners
Cons:
- No spray nozzle included
Star brites Sea Safe Hull Cleaner was definitely one of the top runners for best hull cleaner for us because of its less harsh formula geared toward being safe for the aquatic ecosystem. On top of being safer, it still did a great job cleaning the surface of our test boat despite not having the harsh acids and chemicals often found in traditional hull cleaners. It made cleaning the boat more enjoyable as well without having to worry about the effects of heavy fumes or contact with skin and other equipment. If you don’t need something to remove foreign growth from an extremely abused hull, Star brite Sea Safe Cleaner may be the best hull cleaner for you!
7. Star brite EZ-On EZ-Off Hull & Bottom Cleaner
Star brite has yet another great product in its EZ-On EZ-Off Hull & Bottom Cleaner. This hull cleaner is one of the toughest in their lineup. EZ-On EZ-Off is an acid based cleaner that is the best hull cleaner from Star brite for loosening tough deposits and stubborn stains with a lite brushing.
Container Size:
- 32 ounces
Pros:
- Works instantly on rust, stains, and scum
- Loosens the toughest deposits on boat hulls
- Water based, environmentally friendly
- Special buffered acid to make safer than typical acid based hull cleaners
Cons:
- Best if used with gloves, safety glasses, and good ventilation
- Strong odor
- Can potentially damage metals it comes in contact with if not immediately rinsed
- Does not come with a spray nozzle
Star brites EZ-On EZ-Off Hull & Bottom Cleaner definitely did a great job with making hull cleanup an easy task for us. Being an acid based cleaner, it made quick work of the under side of our boat. On the flip side, it is corrosive and has a strong odor to it. It can also be harmful to trailers and other objects it comes in contact with so it’s important to make sure to cover anything up it may drip on.
As with all acid based cleaners, our recommendation is to wear gloves, safety glasses, and a respirator for maximum protection. We found of all of Start brites cleaners, EZ-On EZ-Off was the best hull cleaner for extremely tough buildup but might be over the top for mild cleaning jobs.
8. Power One Boat Hull Cleaner
Power One Hull Cleaner and Rust Stain Remover is a popular product used not only by marine enthusiasts but anyone looking to use it to remove rust stains and buildup on anything else. Not only is this one of the best hull cleaners but will also do wonders on rust stains caused by hard water on everyday appliances and other surfaces that may see the staining of heavy iron deposits. Power One Hull Cleaner made quick work of the stains on our test boat and we’d recommend it to anyone looking for the same. Below is a few features of Power One Hull Cleaner.
Container Size:
- 32 ounces
- 1 gallon (128 ounces)
Pros:
- Works instantly on rust, stains, and scum
- Fast acting, works in 60 seconds or less
- Odor free, no fumes
- Biodegradable
Cons:
- No spray nozzle included
- Potentially tough on bottom pain
Not only did Power One Hull cleaner do a great job removing the stains from our test boat, there were a few other things we liked about it as well. The smells and fumes while using Power One were much less than some of the other heavy duty cleaners. We felt the product did an excellent job while not having to have a mix of extremely potent chemicals. This could be the best hull cleaner for you if you are looking for something to get the job done but is not overly harsh. Once we were finished with the boat, we can use it for other stained surfaces as well!
9. Boat Juice Exterior
Boat Juice is a newer player in the market that we were interested in checking out. It doesn’t fall into all of the categories for the best hull cleaner in a standard search, however, we wanted to at least try it since it did come up in a few searches. As a cleaner we are excited about a lot of its features. As with each product, there are a few pros and cons that may or may not make this your best hull cleaner! Below is a few features of Boat Juice Exterior Cleaner.
Container Size:
- 32 ounces
Pros:
- Contains polymer wax for added protection after cleaning
- Removes mineral deposits and hard water spots
- Non-toxic and biodegradable
- Multi purpose safe on watercraft as well as trailers and other gear
- Comes with spray nozzle
- Pleasant smell
Cons:
- Slightly under powered for tough, harsh jobs
- Mostly for cleaning hulls after a days use and maintaining the cleanliness
Over all, Boat Juice Exterior is an excellent well rounded product. We did, however, find that even though some companies list it as a hull cleaner, it is more for light duty cleaning and detailing. Even though Boat Juice Exterior may not be the best hull cleaner to remove thick buildups and harsh stains, we wouldn’t say no to a bottle of this any day!
It does a great job cleaning smaller buildups and leaves a nice finish and protection since it contains a polymer wax. This is essential for keeping your hull fresh and clean. We highly recommend this if your best hull cleaner is something quick you want for after each use to maintain and protect your boat hulls finish for years to come!
10. Simple Green Marine
Simple Green is one of the most well known cleaners in any kind of market today. Whether you’re looking for a degreaser, bacteria killer, or marine cleaner, Simple Green has it all! Simple Greens Marine All-Purpose Boat Cleaner is one of the products we tested on our boats hull to compete for the best hull cleaner. It has been formulated to remove the typical marine grime, tough stains, fish blood, and other enemies of your boats hull. Enjoy its safer non acid based formula with no need to be over precautious with handling the liquid. Below are a few key items to note about Simple Green Marine:
Container Size:
- 22 ounces
- 1 gallon (128 ounces)
Pros:
- Removes tough stains, grime, fish blood, oil, grease and more
- Non-toxic and biodegradable
- Multi purpose safe on watercraft as well as trailers and other gear
- Comes with spray nozzle
Cons:
- The 22 ounce container is less cleaner than many competitors
- Slightly under powered for tough, harsh jobs
- Mostly for cleaning hulls after a days use and maintaining the cleanliness
Simple Green Marine All-Purpose Boat Cleaner is an excellent lighter duty cleaner and can be the best hull cleaner for quick or smaller jobs. While it’s not intended for heavy duty or the toughest jobs, Simple Green Marine did a great job on the typical stains we had on our boat. We liked that it came ready to go in a bottle equipped with a squirt nozzle, it’s non-toxic, and very safe to work with.
It’s extremely practical for those who like to keep up with the maintenance of their boats hull instead of taking on one massive cleaning job at the end of the year. If you’re looking for something quick, easy, and tough on standard stains and marine grime, then Simple Green Marine All-Purpose Boat Cleaner is the best hull cleaner for you!
Final Thoughts
We were excited to try all of the different hull cleaners we listed to see what kind of results we got with each. We found a wide range of cleaners that worked on different levels, had different chemical concentrations, and had different ranges of harshness. We hope this review has helped you come to a decision on what might work best for you. Remember, even though some websites or stores may list a product as a hull cleaner, it may or may not be the best hull cleaner for your application depending on how big or small your job may be!
Once you’ve found the best hull cleaner for your job and have finished cleaning, head over to our other article to check out our test for the best rubbing compound that will bring your boats gel coat back to life!
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