Cleaning with TSP

Aug 10, 2020
511
Catalina C25 3559 Rocky Mount
I just got my butt chewed on a FB page for using this to clean mold from my decks. What are your all's thoughts? You'd have thought I was dumping used motor oil by their reactions. We used this for years in vinyl siding and wooden decks. I always thought of it as mild and somewhat environmentally friendly.
 
Jan 11, 2014
11,324
Sabre 362 113 Fair Haven, NY
The big issue with TSP is the Phosphate part. When it enters the water it becomes a fertilizer for aquatic plants. Many states have banned the product.
 
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Feb 14, 2014
7,400
Hunter 430 Waveland, MS
Phosphates got a bad name years ago as ingredient in Laundry Detergents.

I just added some to my vegetable garden as PKN fertilizer We eat the produce and then Emit them down the drain.

Oh My Gosh!
Where does the dissolved Phosphates go?

Oceans

Makes Algae, ocean life eats Algae, Man eats fish...
Life is good...
Jim...

PS: FB is the spreader of the real Fertilizer:poop::poop:
 
Jan 11, 2014
11,324
Sabre 362 113 Fair Haven, NY
Phosphates got a bad name years ago as ingredient in Laundry Detergents.

I just added some to my vegetable garden as PKN fertilizer We eat the produce and then Emit them down the drain.

Oh My Gosh!
Where does the dissolved Phosphates go?

Oceans

Makes Algae, ocean life eats Algae, Man eats fish...
Life is good...
Jim...

PS: FB is the spreader of the real Fertilizer:poop::poop:
Not to start an environmental dispute, phosphates in lakes is a different issue than phosphates going into the ocean.

In freshwater lakes toxic blue-green algae blooms are associated with excess fertilizer in the water supply. In recent years this has been a real issue on Lake Erie due to agricultural run off. Since many lakes take a long time for the water to exchange the concentration of phosphates builds up.

Another problem is the build up a invasive plants such as European Milfoil, Purple loosewort, and water chestnuts which clog water ways and shallow lakes. The plants thrive and then die. After death they rot on the bottom consuming oxygen which affects fish.

TSP is not the biggest contributor to excess phosphate in the water, but it is part of the issue.
 
Oct 26, 2008
6,048
Catalina 320 Barnegat, NJ
I'd be much more sensitive to the effects of phosphates if you are using it on water than if you are using it on land. Washing it directly from the boat into the lake should be avoided! Fertilizer on land-based plants, not so bad!. Of course, washing it into the storm drain is almost the same as washing it into the lake.
 
Apr 11, 2010
946
Hunter 38 Whitehall MI
TSP is actually kind of harsh to use. If it runs down any polished / waxed surfaces it will strip the wax off So your topsides are likely getting stripped of their polish. Finished wood will have the finish eaten off.
The container cautions to use rubber gloves to reduce the possibility of caustic burns as it is highly alkaline.
It can degrade the caulk/sealant from around fittings and ports.

Yes Tri Sodium Phosphate (TSP) does contribute to the phosphate loading environmental concerns but honestly the amount you are using pales in comparison to the over use of lawn fertilizer by lake front property owners, septic systems of lake front homes that are too close to the water and leaching phosphate laden waste, municipal sewage treatment systems, and agricultural run off from farm fields into streams that feed the lakes, etc.

With 44 years in an environmental management career I am always concerned about environmental impact and seek to minimize that impact but frankly harshness of the cleaner and its impact on your boat is something I’d be far more concerned about.
 
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Bob J.

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Apr 14, 2009
773
Sabre 28 NH
I just got my butt chewed on a FB page for using this to clean mold from my decks.
I saw that yesterday & said oh boy, here we go... I wouldn't worry about using TSP long as your boat isn't in the water. Far as FB or any forum, there are those that will always flip out over something if you're not in line with their thinking.
 
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Aug 10, 2020
511
Catalina C25 3559 Rocky Mount
IMG_20210511_200728_676.jpg

It does a stellar job of loosening up the mold. I mixed it pretty weak, maybe 3/4 cup to 3 gallons of water. I wet out sections, let it set a couple minutes and gave it a quick scrub with a stiff brush. I still need to get the nooks and crannies. The whole thing needs and actual wash now.
Not bad though for a boat that hadn't moved in years..