Fender: Anchor Marine - Gone Green

[nigelmercier]

I've got an Anchor Marine fender that is horizontal on my pontoon. It has gone green on one side, only the side in direct sunlight.

Picture shows the white-green boundary, and close up of green area:

Any thoughts what this might be, and how to clean it?

 

[LadyInBed]

Algae?
but that fender isn't green, just slightly discolored!

 

[macd]

The green is chlorophyll, which is really tremendous stuff. Without it you'd be dead

 

[PlankWalker]

Get some UPVC window frame cleaner, does wonders on fenders,

Plank

 

[Fourbees]

For fenders I swear by (at?) magic sponge, aka melamine foam. Also sold as "doktor power" in places like Robert Dyas. It's very effective on fenders, and also for removing stubborn marks on gelcoat.

 

[Colvic Watson]

For fenders I swear by (at?) magic sponge, aka melamine foam. Also sold as "doktor power" in places like Robert Dyas. It's very effective on fenders, and also for removing stubborn marks on gelcoat.

Big plus 1

 

[Fantasie 19]

Big plus 1

Given that those sponges don't contain chemicals, but a paste of stone or pummice, you could probably just as easily use a very fine wet and dry???

 

[Fourbees]

Given that those sponges don't contain chemicals, but a paste of stone or pummice, you could probably just as easily use a very fine wet and dry???

I don't know - I'd be afraid of leaving scratches on the gelcoat. The aforementioned magic sponge is said to be melamine foam, and melamine is a sort of plastic, not stone or pumice.

 

[Spirit of Glenans]

For fenders I swear by (at?) magic sponge, aka melamine foam. Also sold as "doktor power" in places like Robert Dyas. It's very effective on fenders, and also for removing stubborn marks on gelcoat.

Lidl/Aldi have sold these at some stage, labelled as " Magic Cleaning Sponge", or similar

 

[Pcd]

Spray Fairy Power Spray on. Leave for 15 minutes. Rub off and hose down.

 

[Fantasie 19]

I don't know - I'd be afraid of leaving scratches on the gelcoat. The aforementioned magic sponge is said to be melamine foam, and melamine is a sort of plastic, not stone or pumice.

No idea - I just looked at the product description - don't get me wrong they sound damn good and I shall be buying one to see how it works on some old sticky tape adhesive residue

"JML Doktor Power is a safe environmentally friendly Non toxic and bio-degradable hard cleaning stone (paste) made from natural ingredients ."

 

[Fourbees]

"JML Doktor Power is a safe environmentally friendly Non toxic and bio-degradable hard cleaning stone (paste) made from natural ingredients ."

Hmm - interesting! Perhaps I have never read the carton... but it's certainly good stuff. On gelcoat it shifts scuff marks that look permanent.

 

[Colvic Watson]

Doktor Power is great, but it's a polish so it will scratch. It's the melamine pads that are so awesome, no chemicals needed at all.

 

[colvic987]

as said by others, it is great for getting rid of those stubborn marks, but the magic sponges make the fibreglass dull, but a good polish brings back the shine.

 

[VicS]

I've got an Anchor Marine fender that is horizontal on my pontoon. It has gone green on one side, only the side in direct sunlight.

Picture shows the white-green boundary, and close up of green area:

Any thoughts what this might be, and how to clean it?

Algae as suggested

Dilute domestic bleach..... will kill it then the green colour will slowly disappear.

More concentrated bleach will kill it and bleach it more-or-less straight away

 

[nigelmercier]

Tried neat bleach, and the excellent HG mildew remover that I'm not allowed to link to anymore. The discolouration appears to be in the plastic.

 

[Mistroma]

Tried neat bleach, and the excellent HG mildew remover that I'm not allowed to link to anymore. The discolouration appears to be in the plastic.

Our fenders went the same way after being left in the aft locker one winter. Warmer and more humid than usual Scottish winter weather. I assumed it was surface mildew. However, nothing has shifted it over the last couple of years.

Lots of greyish/greenish blotches on the sides, not a lot on top or bottom. Bleach, localised scouring, acetone (small area), petrol, practically everything short of a belt sander. They appear to be permanent marks and not just on the surface.

Spots on your fender are denser, ours are more spaced out. Otherwise very similar, let me know if you find a magic cure (not holding breath).