mildew experiment bleach -vs -

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Sailingsaves

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Nigel offers great advice and answers on here (as well as many other people of course) and he suggested a mildew remover instead of bleach.

As I love experimenting, I did and here are some results sort of.

I did start to overlay the images in photoshop and try to count how many dots or quantify how much mildew was removed, but then I had to move onto other more pressing matters.

Anyway, here are some photos of my "navigators bag" that I left on my boat about 10 years ago (i.e. mildew is 10 years old) boat is long gone alas.
Personally, I found Nigel's recommendation easier to use (spray shower cubicle etc) and less smelly than neat bleach. In the shower, it worked better than bleach for sure.
View attachment 37564View attachment 37565View attachment 37566View attachment 37567View attachment 37568
Key to photos in order: Beginning, bleach wet, bleach dry, HG wet, hg dry.
 
If anything, the bleach before and after pics look somewhat better than the HG before and after pics. Not surprising that there doesn't seem to be much difference really, because the HG Mould Spray is just a dilute solution of bleach and caustic soda.
 
nigelmercier said:
Thanks for that. Did you only apply it once to the bag?

This is the stuff: http://www.amazon.co.uk/exec/obidos/ASIN/B000IU40HQ/dolcetto-21
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Yes, that was one application and approx 30 minutes later. I repeated with just HG the next day and almost all clear.
It certainly DID outperform the bleach in the shower (noticeable difference), but I am too embarrassed to post photos of my manky silicone sealant.
I agree the photos of the bag are not conclusive, but I will be using HG a lot more for lots of other applications.

It was the varying beliefs of people that made me want to try it and the fact that I secretly believed it would be better than bleach because Nigel is right so often. Not trying to lick boots here, but just credit where it's due.
 
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The trouble with bleach is, depending on the strength and the material to which it's applied, there's a significant risk that large chunks will fall out of the fabric at a later date. Seen it it happen with jeans, curtains and blinds.
 
The MSDS from HG states the beach and caustic concentrations are 1-5%. So about a teaspoon of caustic crystals in a litre of cheap diluted bleach. £0.30 per litre instead of £5.75 for 500ml!
 
nigelmercier said:
Fair enough. I did say in the other thread that there must be something in it that made it work better than bleach alone.

Looks like we have a new home-brew solution: what are the concentrations.
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Astonish Mould and Mildew remover, about a quid a spray bottle in the local cheap shop, ingredients, bleach and caustic soda. Is it worth fannying around?
Stu
 
All well and good.

But one of my degrees is chemistry and I would not mess around mixing stuff (fair enough that I have probably forgotten most of it).

I have bottles of caustic soda for cleaning things (must be careful with it). I have bottles of phosphoric acid and lots of citric acid, but I would rather buy HG (seeing as it works) than try to make my own and possibly go blind. (Will look out for the Astonish stuff if it is cheaper than HG)

Nigel was right. It is better than pure, strong bleach and as he said, possibly because of something extra in it. If it is the inclusion of caustic soda we now know why it is better than bleach, but as a poster pointed out, there are dangers to the medium it is used on (as well as to one's self), so I won't be mixing any concoctions.

I was most pleased with my navigator's bag (10 years of mildew gone and no damage or bleaching of colour). Shower looking better. Shower curtain all ok. Patio door blinds cleaning up nicely (cold and damp gets in there). No damage to anything so far, all in an easy to use spray bottle for a fiver.

I for one will seek Nigel's apparent expertise out in the variety of topics he has demonstrated time and time again. There are so many clever people on here with solutions to all sorts of problems_ you should all create a Party and run the country.
Thanks.
 
I too would advise strongly against mixing bleach with anything for safety reasons, and household bleach typically contains sodium hydroxide (caustic soda) anyway (see e.g. http://www.chm.bris.ac.uk/motm/bleach/bleachh.htm). So it wouldn't simply be a case of 'a peck of this in a firkin of that'.

My other concern is the same as elton's, that household bleach unless highly diluted could cause damage to the fabric that may well not be apparent for some time. I'd start with a percarbonate-based ('oxygen') stain remover and progress to a proprietary mould stain remover (or very dilute bleach if that were unavailable), all with thorough rinsing. There is also of course the timeless advice to 'test on a small inconspicuous part' first.

If all else fails (and with mould spots on certain fabrics it will, I believe) you can take the advice of a poster on Mumsnet (http://www.mumsnet.com/Talk/good_housekeeping/768168-How-to-get-mould-out-of-clothes/AllOnOnePage) and consider dyeing the item a dark blue or purple - if it will take a dye and not run to leave your boat or anatomy purple, of course. For those of an experimental bent, another poster on that thread suggests soaking the item in a basin of water with some penicillin dissolved in it. And no, they were not being serious - but did take someone in :).
 
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Hydrozoan said:
For those of an experimental bent, another poster on that thread suggests soaking the item in a basin of water with some penicillin dissolved in it. And no, they were not being serious - but did take someone in :).
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Are you sure they werent serious? After all it is a biocide of sorts. And if you work in the NHS, its no doubt readily available FOC - well to you if not the taxpayer.

I did once meet a newly retired Swedish gynocolgist who was setting ouy for his retirement round the world cruise. Since the Swedes are pious about what you can put on your boats bottom, he had raken the very weak antifoul they are allowed and mixed it with qualtities of swedish NHS chloromycetin. He swore that this made the best antifoul ever and as with the above alternative, it was FOC..
 
Bosun Higgs said:
Are you sure they werent serious? ...
Click to expand...

Well, they said it was a jest and someone said they'd been taken in - see link. I can't see why an antibiotic should be any good at removing the coloured residues of mould merely because it is produced by (a different) mould. But it takes a moment to see beyond the obvious mis-connection when one is reading the thread.

As to the Swede, I suppose an antibacterial could act against bacterial slime, but am not sure if it would anything at all against barnacles, algae etc. And I do hope he doesn't misuse antibiotics any longer - see https://medium.com/p/892b57499e77. Just one statistic: before antibiotics "... one out of nine people who got a skin infection died, even from something as simple as a scrape or an insect bite". In fact as you may know, the first trial of pencillin was on a man who had developed a terrible infection from a scratch from a rose thorn - it was rapidly effective, but they hadn't enough to continue the treatment and he died. Sorry, I referred to penicillin first so I must not become pious - but antibiotic resistance is a real menace.

The unusual antifouling ingredient that has interested me is chilli powder, on which there have been many threads here - but I like curries.
 
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Have just pointed SWMBO towards this product after reading the OPs findings. Works a treat and has just removed 99% of the black mould that ordinary un-diluted bleach wouldn't shift from the shower tiles and silicone. Yes it costs £5.75 but the smell alone would suggest that you would not want to mess about with concocting your own version. Thanks also to Nigel as it means I don't have to redo the bathroom quite so quickly!
 
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