Formula B vs Formula A - Mold removal and prevention - what am I missing? (Practical Sailor Magazine)

Aug 23, 2023
29
Paceship PY23 Gulfport, FL (Tampa)
Formula B vs Formula A - Mold removal and prevention - what am I missing?

The practical Sailor concoctions (recipe below)

Seems like they are still citing both formulas but it's not clear which one is better, or, which one is better for what. Is one better for removal of mold and other better at preventing mold? Is formula B the shizzle since its the latest version?

Formula B
1 quart hot water
2 tablespoons baking soda
2 tablespoons Borax
1 tablespoon TSP
Formula B was the second-place performer in the liquid group. It was certainly the best value. It cleaned well, prevented mildew from returning to the carpet, and greatly slowed mildew infection in the moist-environment test in the lab.

Formula A
1 quart hot water
1 tablespoon baking soda (sodium bicarbonate)
2 tablespoons washing soda (sodium carbonate)
2 tablespoons trisodium phosphate (TSP)
Much like Concrobium (which it is modeled after), our homemade Formula A removed the mildew from test carpet on board and kept it away, even though the area got wet again. It was also very effective in the moist-environment lab test.
 
Mar 26, 2011
3,823
Corsair F-24 MK I Deale, MD
Both are similar. Formula B is slightly better at preventing mildew, but borax is not available in the EU, so Formula A works.

They also prevent mildew just as well without TSP, which is getting harder to find, by upping the other ingredients slightly. However, cleaning ability will be very slightly reduced. The primarily effectiveness is provided by the mildly alkaline residue that prevents the return, but borax is also mildly antimicrobial. It is important that the formula not contain organic soaps or detergents, which themselves become mildew food.

A low concentration (~ 0.1%) of BAC (benzalkonium chloride) can be substituted for borax. Wet-and-Forget is basically a BAC solution with some surfactants (read the SDS).

The main thing is how you use them. A pump up sprayer works well for application. Soak, scrub, repeat. And on the last pass, do NOT rinse but rather leave a residue. The concentrations are set so as to leave an apropriate residue to prevent t he return or mildew. Vacuum as dry as practical with a shop vac with an upholstery attachment or an upholstery cleaner. Dry with a fan.

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Why no borax in the EU? Borax is slightly toxic and if used stupidly it can be troublesome. Read up.

Boric acid and your health - Canada.ca
Boric acid, also called boron or borax, is found naturally in the environment. It can also be used in common consumer products. Learn about this chemical and if it's safe for Canadians.

www.canada.ca
www.canada.ca
Do NOT increase the concentrations above those listed; it won't work better anyway. Do not treat clothing or bedclothes in the manner described; they must be well rinsed after treatment to kill the mildew. Formula B was only developed for seating upholstery and fabric hull liners.
 
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Aug 23, 2023
29
Paceship PY23 Gulfport, FL (Tampa)
Thank you! ... please clarify the following-

"Formula B was only developed for seating upholstery and fabric hull liners " so are fabrics the intended and only things to clean/treat with B? does B have other applications?

I'm looking for something for mold circles/spots (nickel sized) in the inside of a fiberglass boat - ceiling and walls that are fiberglass/gelcoat. What would you recommend for that?
 
Apr 8, 2010
2,190
Ericson Yachts Olson 34 28400 Portland OR
I do love those enthusiastic ads for the various cleaners with their bragging about total satisfaction with little or zero work.... but getting rid of and maintaining a clean and odorless interior always will take effort. (No matter how enthusiastic those paid models are on the telly -- or some paid "influencer" on the web.)

Wield that Bristle brush, repeatedly, and something strong like "Softscrub" and lots of wet and dry rags and a water bucket. Very little Fun, but considerable satisfaction!
And, once cleaned up, stop all of the leaks and then maintain a dry bilge.