Unshiftable loo stains

Oct 03, 2012 46 Replies

Two areas of darkened encrustation below the waterline, which refuse to yield to bleach and similar domestic cleaners and which even direct scrubbing cannot shift. Any suggestions? Perhaps draining the loo (by siphoning off the water?) and then retrying the cleaners is the way to go?



Many thanks.



strong sulphuric acid is The One.

NT

And leave it overnight.

aka "Brick Acid", available from some sheds and most builder's merchants.

Or hydrochloric aka "Spirits of Salts" - available from all good proper hardware stores.

During one of the water shortages, I found that urine left to mature in the pan cleaned it very effectively.

Colin Bignell

Many thanks for all the speedy replies. I have some Ataka limescale remover, which usually proves very effective, to hand, so I'll try that first. Then if that fails it will be onto the various other acids.

Bert

Brick acid *is* hydrochloric acid. N'est pas?

Get the end of an old blunt table knife in there and scrape the stuff off. I had that and the only way to shift it was by brute force.

Bleach isn't a cleaner - in so far as it does anything in this respect, it tends to remove the colour from dirt so you can't see it. In many cases, the effect is only temporary anyway.

Yes.

Always make sure you have flushed one chemical/cleaner well from the toilet and pipework before trying another. There are many combinations which react badly together, and in a few cases you might not be able to get out of the room fast enough.

Hydrochloric acid - as strong as you can obtain. But don't splash it about too much.

The trouble with sulphuric acis is that it leaves insoluble sulphates, which are just as difficult to get rid of - or so I'm told. I'm not a chemist.

N'est-ce pas

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'est-ce_pas

I think you are talking about urea oxalate or something like that. Bladder stones and the like.

Just think of it from the point of view of an oyster.

Harpic Power Tablets - put one in either before you go to work or last thing at night and leave as long as possible. Repeat until the limescale has all gone and then do weekly/biweekly as required. At the same time I normally squirt a little Viakal around the bowl to get the limescale there.

Paul DS.

Are we talking limescale tinted by um excrement? There are some spray on preperations that seem to break it up to a sandy substance, but the real issue, if you pardon the pun is the stuff left around the bend, and this tends to pong a lot when you empty the look to do the job on the stuff at the bottom Still needs scraping, I use an old blunt kitchen knife, but I reckon that the glaze has minute cracks and the stuff grips to that. I guess the only answer is something very agressive like an acid based stuff or a new loo.

Brian

HCl works ans is usually ok, but on occasion can permanently disfigure the ceramic. More likely to happen on old goods. Sulphuric is The One to use, sold for drain unblocking at plumber's merchants. Do treat it with real care, its very vicious.

Knives can scratch the ceramic, and are work that simply doesn't need doing.

I wouldn't waste time & money on brand name descalers. They'll take all day if youre lucky, at a silly price.

NT

No it isn't.

Handling strong sulphuric is more dangerous than strong hydrochloric acid and not as good. Calcium and iron chlorides are more soluble. Sold as "brick acid" in good hardware stores.

Sulphuric (aka battery acid) and some table salt will do at a pinch.

Significant heat is generated when you dilute strong acids - potentially enough to boil water (and seriously dangerous to eyes, hands etc. if you are stupid enough to add water to strong acid).

96% sulphuric. Sold in commercial cleaning supplies places, or some hardware shops.

Hydrochloric has the risk of visibly disfiguring the glaze.

IME scale is soluble in any acidic solution but, if it has been allowed to build up to a crust, it will take time to dissolve. As it's below the water line, a squirt of vinegar at night should start to yield results after a couple of days. I have to say the recommendations of sulphuric acid are somewhat reckless given what a beast it is to store and use. Sulphamic crystals (aka Fernox descaler) is just as strong (PH1) but also safe to use and store. Trouble is, you don't get to put your check shirt on and behave like a macho man :-)

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