Killing mold for good?

[Wotname]

AFAIK.

Bleach only works on hard non porous surfaces (glass, ceramic etc). It will not penetrate porous surfaces (e.g. wood) leaving the mould spores deeper down in the material active. In some cases, this allows mould to become immune to the bleach. It does of course bleach the surface mould so it does look mould free.

Vinegar kills 82% of the different moulds but has no effect on the other 18%. It does however penetrate porous surfaces quite well.

Borax (which is alkaline IIRC) is very effective as noted upthread and when used in conjunction with a vinegar treatment, it becomes even better.

I have found from personal experience that clove oil (and tea tree oil) applied post cleaning certainly does delay the return of mould. If you doubt this, try it yourself; apply to half the area you have cleaned and compare the time taken for the mould to re-appear on both areas.

[El Pinguino]

We wipe down with eucalyptus oil.... seems to work...

Trouble spot in the past was around the galley.... we get very little mould there now.

Boat is usually shut up for three months at a time... we don't ventilate it.. apart from what the dorades provide.
My logic is that when you leave the boat the moisture in the air inside will condense out over a short period and you then have a boat full of dry air....
By ventilating you just keep on bringing in more wet air.....

I seem to recall reading years ago that the US Reserve Fleet in the James River and elsewhere was sealed up with no ventilation. I assume those people knew what they were doing.

PS This has all been when laying up south of 40º South.
How it will have worked this time round - at 2º South - remains to be seen......

[mchlsutton]

Going to cast a third vote for concrobium. I've used it in multiple situations, both home and boat, and it just works. I keep a spray bottle on our boat at all times.

Cheap, available at box stores like home depot or Lowe's, and entirely benign (except to mold!). Another benefit is that you can rent an aerosol mister, fill it with Concrobium, and leave for a couple of hours while it penetrates every air space that mold does, even the ones you can't see which will continue to harbor spores. Just cleaning the surfaces you can reach in a boat will never completely eradicate a mold issue.

The mister will require a power source, but if you can dock for a couple of hours to access shore power you hopefully won't have to deal with this issue again. The only complaint I've ever had about this product when using the mister it's that it will leave a fine, powdery film on surfaces which you then have to wipe off. Small price to pay for success.

[zengirl]

I have that same pro breeze dehumidifier, only the next size up. I love it!

[redhead]

Up here in the Pacific Northwest (where I truly believe they invented mold) most everyone recommends "30 Seconds". I've been using it for the last 5 years with good results. The down side is that it comes back. I don't know if that's just the nature of living here, or if the product is leaving some residual mold.

What I like best about 30 Seconds is that it works like a charm on Sunbrella with no ill effects.

I'm definitely going to try the Concrobium and the Borax/TSP mixture. Nothing to lose.

[peterbeale]

Ozone is excellent but you must not breath it. If it is hard surfaces also wipe down with vinegar. It it is on porous surfaces you have a problem as the mould will have penetrated inside, and that is hard to kill.

[Cheechako]

Without power that's tough. minimally I would get some little solar fans to create airflow for one thing.
If you want to get exotic get an Ozone Generator, a solar panel, a small invertor and a time relay. Set the relay so that it turns the Ozone Gen on for limited amounts of time each day so the solar keeps the battery up with the amperage draw...

[Disailor]

I put a 4x6 (+\-) SS Louvre vent in my top hatchboard & raised the FWD hatch about 1/2 " (1cm). Dried the bilge & lost the mold.

[GerryL]

I too have used this formula from Practical Sailor. It's easy to make and effective. I seem to recall the article said that one could double the concentration of powders for bad cases, but no more.

Originally Posted by CarlF

Use this home made cleaner that tested best by Practical Sailor. Clean off the mold with it then wipe a bit more on and let it dry. The residual will retard mold coming back. The ingredients have no smell, don't stain and are all used in food products.

1 quart hot water
1 tablespoon baking soda (sodium bicarbonate)
2 tablespoons washing soda (sodium carbonate)
2 tablespoons trisodium phosphate (TSP)

But you also have to get some air movement. It doesn't take much. Get a small solar panel (10w) and just tie it to the deck. Put a computer fan in a dorade vent or a port that rain doesn't come in with tape. You don't need a controller - just hook it up directly. These Noctua fans are great and use less than 1 watt of power. It works better to use the fan to exhaust air.

https://www.amazon.com/Noctua-NF-P14...7Z5H4HY2B6TC8T

[avotrejoyeux]

You are getting good input from a helpful group. The following is another alternative that worked for us. We were recently in Golfito, Costa Rica for 8 months. While Golfito is a warm mold generating area, believe me, it is wet. Exteriors, canvas and lines turn green with mold and very likely algae. We learned that ventilation was counterproductive for managing mold for our interior; and, as another post shared was a means of making sure the interior stayed high in humidity. Our success in stopping the interior mold included closing the boat entirely. We tried various solutions to wipe down the teak and formica surfaces and finally discovered that a complete wipe down with Kirkland (Costco) disinfecting wipes with a closed boat was completely successful. We typically left the boat for 3 to 5 weeks at a time and could come back to a clean and mold free boat.
We had some leaks given the amount of rain nearly every day; hence, we had some moisture; even so, no mold. The disinfecting wipes are a staple for keeping our boat clean, fresh and mold free.

[Cadence]

Originally Posted by Bigjim

My boat was on the hard for years. She's been back in the water for two years now. She had lots of water intrusion and I've fixed many of the leaks, but she's still pretty wet.

The issue that just arose is mold. I thought I had it licked last year. I washed off all the mold on all exposed surfaces and had a fan running through the summer which kept it gone.

But now it's winter and she's back on the hard and not plugged in. So, I can't run fan full time anymore. I don't have solar installed yet so the interior is pretty stagnant. I went on board the other day and, even though it's below 30 degrees, lots of the exposed surfaces have that mold again.

First, what cleaner do you recommend using to get rid of the mold that doesn't present other problems or health risks?

Second, is there a product I can use to treat the surfaces to keep it from coming back?

Try a few drops of iodine in a squirt bottle of water.

[thinwater]

Originally Posted by redhead

Up here in the Pacific Northwest (where I truly believe they invented mold) most everyone recommends "30 Seconds". I've been using it for the last 5 years with good results. The down side is that it comes back. I don't know if that's just the nature of living here, or if the product is leaving some residual mold.

What I like best about 30 Seconds is that it works like a charm on Sunbrella with no ill effects.

I'm definitely going to try the Concrobium and the Borax/TSP mixture. Nothing to lose.

Bleach + washing soda + surfactant.

[Sunday Driver]

I’ve had the best results using Concrobium. It kills more variety of mold than bleach or vinegar. I wipe down moldy surfaces and it’s months before I need to touch up. I bought it at Lowe’s.

[jhulmer]

I have had really good results with Hydrogen peroxide! No smell either!

[thinwater]

Originally Posted by jhulmer

I have had really good results with Hydrogen peroxide! No smell either!

But it leaves no residual to prevent return. It can also bleach some fabrics. Finally, if diluted from 3% drugstore bottles, it is no longer germicidal; it must be used full strength.