Soap is soap, right? And what about spray wax? Well, the ones we tested all gave good results but weren’t exactly alike. We wanted to know which of the popular brands — and one new brand — would do the best job for the right money. So we put them through the ringer in our latest BoatingLAB test and found that each had some unique capabilities.

How We Tested
Environmental Concerns: All detergent products eventually biodegrade, but we were looking for particular environmental benefits or hazards for use around the water because when you wash your boat, stuff gets in the water, either directly through the scuppers or indirectly via street gutters. Phosphates are not used in any of the soaps we tested. High-sudsing soaps can help lift dirt and grime, but the foam, even though biodegradable, is unsightly around marinas.

Mixture: How much product per gallon of water is recommended? Some instructions were vague, such as two or three capfuls per gallon or a capful per bucket. We would encourage the manufacturers to be more specific; most boaters use 5-gallon buckets to wash their boats. We calculated a bucket to equal 1 gallon.

Cost Per Use: Boat Wash: Container cost/[container size/(ounces per gallon x 2)]. We assumed we’d use 2 gallons per wash.

Spray Wax/Detailer: Ounces used to spray one coat on the entire outer hull of a 25-foot boat x cost per ounce.

pH: A neutral pH of 7 is important in maintaining your boat’s finish. Washes that are too acidic (a pH of less than 6) can quickly destroy paint and gelcoat. We tested pH with litmus paper. Household soaps, like dish soap, are more acidic; for instance, Dawn tested to a pH of 5.

pH Mixed: It bears noting that, when mixed to directions, all the soaps, regardless of the concentrate’s pH, hit the scale at a perfectly neutral pH of 7 when mixed. The main risk of acidic or alkaline soap concentrates is spillage of the concentrate itself.

Viscosity: Some soaps were syrupy in their undiluted forms, and some were downright gloppy, which made us feel we were getting more for our money. But we found no correlation between viscosity and efficacy or economy in our tests.

Spot and Streak-Free Dry: We dirtied the boat with a day of scalloping on Florida’s Gulf coast. An hour after loading the boat on a trailer, we washed sections of the boat with each product. First, we washed and let dry, noting spots and streaks. Some soaps, like Awlwash, are formulated to sheet, or run off the surface quickly, leaving little or no residue. After that test, we washed again, rinsed and left to air-dry, noting that all the candidates gave a reasonably good and comparable result when properly rinsed.

Water Beading: Water beading is a sign of surface tension. You expect to see it on a coat of wax, but it causes spotting, unless you wipe it off.

Observations: Our test crew of four people observed the wash process and results, and then rendered a collective opinion.

Mothers Marine Spray Wax
$15.43; amazon.com

Spray this light wax on, then wipe the area to be cleaned with a microfiber towel. Let dry and wipe off the haze with a clean cloth. Mothers touts it as a booster for your wax job or a stand-alone product when used frequently. It is recommended for gelcoat, paint, rub rails, metal and more.

Environmental: No noted hazards
Container Size: 24 ounces
Cost Per Use: $5.14
PH: 7
Water Beading: Water beaded heavily.

Observations: We sprayed it on and wiped to a uniform coating. It dried and chalked, and then cleaned off easily, leaving a mirrorlike finish.

Star brite Sea Safe Boat Wash
$8.99; westmarine.com

Star brite says three capfuls of its soap in a bucket of water will clean a 25-foot boat. We used 2 gallons of water in our test. Sea Safe has a fruity smell that we liked and good sheeting action that intended to let the soapy water run off along with the dirt.

Environmental: Star brite makes a special effort to create products safe for our waterways, since all cleaners eventually end up in them. It contains no phosphates, and its low-suds formula is intended to disperse and degrade quickly.
Container Size: 16 ounces
Mixture: 3 capfuls (½ ounce) per gallon
Cost Per Use: 56 cents
PH: 6
PH Mixed: 7
Viscosity: High
Spot and Streak-Free Dry: This was nearly as streak-free as Awlwash.
Water Sheeting: Good sheeting resulted in few streaks.
Water Beading: None observed.

Observations: Sea Safe Boat Wash smelled like Bass Pro Shops’ boat wash and gave comparable results. We think we could’ve washed the outside of the boat with that gallon, but the inside was going to take close to another one.

Awlgrip Awlwash Concentrate 7324
$26.80; amazon.com

Designed to be pH neutral and gentle on Awlgrip topcoats, the product is also ideal for Interlux coatings and gelcoats for its gentleness and ability to lift dirt without harsh chemicals. It contains no acids, alkalies or abrasives.

Environmental: Product is 100-percent biodegradable, but it can cause eye and skin irritation with contact. Prolonged contact may cause cancer.
Container Size: 32 ounces
Mixture: 1 ounce per gallon
Cost Per Use: $1.68
PH: 7
PH Mixed: 7
Viscosity: High
Spot and Streak-Free Dry: Without rinsing, the surface-sheeting action of the soap left the section nearly streak and spot-free.
Water Sheeting: Awlwash left little residue if allowed to dry without rinsing.
Water Beading: No water beading was detected afterward, as expected with a pure soap.

Observations: There is a built-in measuring device on the bottle to help mete out the correct dosage. Sudsing was moderate in the bucket, but when we left it on the boat, 90 percent sheeted off, even without rinsing.

Bass Pro Shops Premium Boat and RV Wash
$13.99; basspro.com

It’s made with cleaners and degreasers to remove road grime, oil, dirt and grease without damaging wax or polish, or harming gelcoat or paint. It has a pleasant blueberry smell. The directions called for three capfuls per gallon.

Environmental: It contains no phosphates. Its moderate sudsing meant no unsightly residue on the driveway or water.
Container Size: 32 ounces
Mixture: 3 capfuls (½ ounce) per gallon
Cost Per Use: 44 cents
PH: 6
PH Mixed: 7
Viscosity: High
Spot and Streak-Free Dry: This was nearly as streak-free as Awlwash. It was a product we would definitely choose to use again. Water Sheeting: Good sheeting resulted in few streaks.
Water Beading: None observed nor expected. Sheeting of the water, which sloughs the soap off with suspended dirt, is the goal.

Observations: This product smelled, looked and worked much like the Star brite boat wash. Additionally, the soapy water sheeted off nicely, leaving a clean hull.

Meguiar’s Gel Wash 54
$9.99; westmarine.com

Blended with conditioners and optical brighteners to enhance shine and color brilliance, this soap uses highly concentrated detergents that are neutral to gelcoat, lifting dirt, grime and grease without taking up wax or finishes.

Environmental: It can cause skin and eye irritation.
Container Size: 16 ounces
Mixture: 1 capful (1/3 ounce) per gallon
Cost Per Use: 43 cents
PH: 7
PH Mixed: 7
Viscosity: High
Spot and Streak-Free Dry: This formula left more streaks when allowed to dry.
Water Sheeting: One of the better formulas to drip-dry.
Water Beading: None observed.

Observations: The aroma may be psychological, but it kept us believing the soap was working. The label calls it a high-sudsing product, and it was right. The suds had legs and clung to the hull. In our air-dry/no-rinse test, that actually caused more streaks than any of our other products, but when rinsed promptly, the results were good. With our navy-blue hull, we couldn’t get a take on the touted optical brighteners, but we liked the finished product.

Grampstr’s Pride Reflect Boat Soap
$11.95; grampstrspride.com

Nontoxic and biodegradable per the label, Reflect is said to be a highly concentrated and low-suds formula. Low suds is preferred to high suds for air-drying, since suds can linger and spot the cleaned surface as it dries.

Environmental: Nontoxic and biodegradable per the label.
Container Size: 32 ounces
Mixture: 2 to 3 ounces per bucket
Cost Per Use: $1.12
PH: 7
PH Mixed: 7
Viscosity: Low
Spot and Streak-Free Dry: No visible streaks appeared after drying without rinsing; contrary to best practices, we used it in direct sunlight.
Water Sheeting: This was comparable to Awlwash for good sheeting action.
Water Beading: None observed.

Observations: It smells like only soap, lacking the perfumes of competitors. When washing where water is premium — say, in island marinas where water is sold by the gallon — its clean sheeting action without rinsing is an advantage. Results are still better with rinsing. Some biodegradable bottles quickly become brittle and breakable in the elements. This bottle can take the heat.

Bass Pro Shops Fast Shine
$10.99; basspro.com

Its heavy but pleasant blueberry smell lets you know it’s leaving the spray nozzle. It is formulated with polymers that shine the surface and leave a UV-protective layer that also protects against salt, corrosion and moisture.

Environmental: Contains surfactants and is an eye irritant.
Container Size: 22 ounces
Cost Per Use: $3.66
PH: 7
Water Beading: You expect water to bead up on a surface after wax is applied, and this one did not disappoint.

Observations: We sprayed the detailer on and evened the application by wiping it with a microfiber towel, rubbing in cross patterns for even coverage. Following up with a fresh towel improved the results. It’s ideal for detail cleaning and waxing.

Star brite Ultimate Boat Guard
$15.99; amazon.com

Star brite has made highly demanded cleaning supplies by adding PTEF, a form of Teflon polymer trademarked in 1945. This product seals finishes, and repels the staining and chalking of gelcoat. It’s touted to be UV-protective and ideal for marine paint, gelcoat and metal-flake finishes.

Environmental: It is an eye irritant (they all are, so use eye protection) and contains isopropyl alcohol.
Container Size: 22 ounces
Cost Per Use: $5.81
PH: 7
Water Beading: Water beaded heavily.

Observations: This spray detailer spread well and easily for uniform coverage. Rubbing it in with one microfiber towel and wiping it dry with a second towel gave best results.

Paste Wax or Spray Wax?
Spray-and-wash detailers are a boater’s best friend. Polymers contained within them leave a UV-protective coating and a shine that looks great, though only temporarily. Paste wax always offers more durable protection, but regular use of the spray waxes we tested can save hours of paste wax reapplication by lengthening the life of wax coatings. With weekly use, even without paste wax, spray waxes go a long way in protecting gelcoated fiberglass.

When used with microfiber towels, their unique formula helps lift minor dirt without scratching the finish. However, don’t be stingy with the spray. Polymers suspended in the formula must penetrate the gelcoat surface to properly do their job. If used too sparingly, streaks will appear in your shine.