BillV wrote:

"Ian Stirling" wrote in message
...
BillV wrote:
snip
The mold you get on silicone sealant seems to be embedded within it.
My theory is that its the acetic acid thats used to cure it going
mouldy.

Nope.
The acetic acid is gone after it cures.
When you stop smelling vinegar, it's gone.
Well there must be something in the body of the silicone that goes mouldy.
I've seen it so many times where even good quality silicone with fungicide
has been used.

I don't think it's quite that simple.
I think it's just that mould can live in the most precarious ecological
niche.
Inside the silicone, there is some retained water, and some limited
nutrients that percolate in.

Mould has been found in explanted breast implants, living on the
glucose and other stuff that diffuses through the walls of the
implant.

When its cut off it can be seen that the mould is inside the bead so
external application of e.g. bleach won't work.
The non-silicone sealants don't seem to suffer from this.

I think it's just that silicone is by nature pretty inert, and somewhat
porous.
Water and nutrients can diffuse into the bead, and fungicides may leach
out, or be ineffective to certain strains.

You could try silicone eater but I've had limited sucess with that.

Its down to hard work with lots of scraping and cutting.

A nice sharp scraper makes it not too bad at all.

If its on a plastic bath or shower tray you have to be extremely careful not
to scratch the item.

Very true.

Also getting it out of the gap can be very tedious.
Of course, if the original stuff wasn't stuck down too well to begin with
then it is easy to remove. :-)