Mold in bathroom sink caulking

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Greentea

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What would be the best way to get rid of the mold that's circled in red in the picture below? It's basically developing in the caulking where the sink meets the counter. We have noticed this for about a year. Will this be hard to remove? There must be a lot of mold inside the caulking?

normal_1532277322-mold.jpg
 
Welcome.

It's not in the caulking, it's on the caulking, wipe with bleach.
 
That would be great! How is this happening? Why is there mold on the caulking and how do I prevent this?
 
Mold does not happen instantaneously, it results from warm moist air, and while the balance of the lav surfaces are exposed to evaporation, that part of the under-shot of the lav/counter directly above the drain have the least exposure to light and air circulation.

I've told my customers for years, with the towel you just dried of with, wipe the shower surfaces off and your grout and caulk will stay relatively clean and mineral free, or pay too have it professionally cleaned.

In the case of your lav, just a Kleenex or wad of toilet paper and done.
 
Just tried to rub it off and no luck. It really looks like it’s in the caulking. The color looks a little faded. Is it possible there is some mold developing inside this gap? Will this be hard to remove?

Thank you
 
To me, even when I zoom in on your picture, it looks like granite under the caulking. If the bead of caulking was thicker, you would no longer see the granite. Use some blue tape, re-caulk over the old caulk, pull the tape and call it a day.
 
Mold, left untreated, will discolor the caulking and if the caulking was not finished to a smooth surface, adhered to both the sink and underside of the granite it may have penetrated.

As suggested, you can skim over the caulking, or you can remove it and start over.

If the caulking is not pliable, it's probably silicone, which is the worst, but common to a lot of tradesman, and will take time to remove with a razor scrapper.

I use POLYSEAMSEAL which works with your dampened finger, is paintable and remains pliable for years.
 
The only way to remove the stained caulking is to remove the caulking(a very tedious task). First make sure that the current caulk is not the only thing holding the sink to the granite. Then razor knife the old caulk out to the best of your abilities.
When you reapply the caulk only use 100% silicone. It offers the best for a mold free look that you can get. Polyseamseal will harden like glass in a year or two, making the next time you do it again a complete nightmare.
 
I have no point of reference beyond 30yrs. and that customers polyseamseal at the lav and Kohler/Tile tub surrounds, yesterday, were still pliable.

I've used polyseamseal for over 35yrs. and never bought into silicone.

I warranty my work for as long as the original contracted with, occupies that dwelling, and I don't do warranty call backs, yet.
 
Some results may vary. I only have 20 years into this but more problems with polyseamseal then silicone. It could be the climate. I can only speake from past experiences.
 
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