Muriatic Acid

CJ13

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I find Muriatic Acid excellent for dosing the toilet valves/ seals etc to keep them free of 'muck'. I used to change Joker Valves at least once a season, but since I've been using it no problems at all.
In Italy it was readily available from Supermarkets (Acido Muriatico). Where can I buy it in Greece, specifically Preveza, and what does the label say?

Thanks,
John
 
Muriatic Acid is another name for Hydrochloric Acid. You can buy it diluted in any supermarket, look for the orange plastic bottles with a black cap. They cost about 50 cents each.
 
I find Muriatic Acid excellent for dosing the toilet valves/ seals etc to keep them free of 'muck'. I used to change Joker Valves at least once a season, but since I've been using it no problems at all.
In Italy it was readily available from Supermarkets (Acido Muriatico). Where can I buy it in Greece, specifically Preveza, and what does the label say?

Thanks,
John

You may find it in "swimming pool shops" cos they need the same stuff to adjust acidity levels in pools....
 
Muriatic Acid is another name for Hydrochloric Acid. You can buy it diluted in any supermarket, look for the orange plastic bottles with a black cap. They cost about 50 cents each.

You do need to search for it sometimes, they hide it away in unexpected areas of the shop. But as Tony says it is available in the vast majority of supermarkets.
 
Never used hydrochloric acid - is it safe to use with 'nylon' valves and standard heads/holding tank 'rubber' pipework?
Also my holding tank is aluminium (as is the boat) so would there be any issues here? At present I dose with Leesan Descale a couple of times a year to get rid of scale formed in valves, pipes and holding tank as a product of the urine/seawater mix. As have to source this in the UK it would be better to find an alternative in the Eastern Aegean (Leros) where Seren is based for the year.
 
Never used hydrochloric acid - is it safe to use with 'nylon' valves and standard heads/holding tank 'rubber' pipework?
Also my holding tank is aluminium (as is the boat) so would there be any issues here? At present I dose with Leesan Descale a couple of times a year to get rid of scale formed in valves, pipes and holding tank as a product of the urine/seawater mix. As have to source this in the UK it would be better to find an alternative in the Eastern Aegean (Leros) where Seren is based for the year.

You don't want hydrochloric acid anywhere near aluminium. The acid will react quite violently with aluminium a rapidly dissolve it!

http://www.youtube.com/watch?v=RzLmbmh59-g
 
You don't want hydrochloric acid anywhere near aluminium. The acid will react quite violently with aluminium a rapidly dissolve it!

http://www.youtube.com/watch?v=RzLmbmh59-g

Thanks Tony - I thought as much with the 'concentrated' version but my post queried the 'dilute/domestic' version. Great UTube clip so won't be adding any to my holding tank!
Any comment on the desirability of using it from head to sea via pipework, Jabsco tri-valve and nylon seacock only?
Any other suggestions out there for clearing the pipework up to and including the aluminium holding tank?
Owen.
 
You don't want hydrochloric acid anywhere near aluminium. The acid will react quite violently with aluminium a rapidly dissolve it!

http://www.youtube.com/watch?v=RzLmbmh59-g

I haven't seen the clip yet. However, you want to avoid putting pure aluminium anywhere near salt water as well as it fizzes away and dissolves quite rapidly. Fortunately, the alloys used in boat hulls are much more stable. :D
 
Thanks Tony - I thought as much with the 'concentrated' version but my post queried the 'dilute/domestic' version. Great UTube clip so won't be adding any to my holding tank!
Any comment on the desirability of using it from head to sea via pipework, Jabsco tri-valve and nylon seacock only?
Any other suggestions out there for clearing the pipework up to and including the aluminium holding tank?
Owen.

Disregarding the aluminium tank for the moment, filling the hoses with hydrochloric acid is a rather inefficient way to remove the insoluble salts that build up in them. It will work eventually but it will take a lot of acid and several days. Mechanical methods are far more effective, the old advice to bang hoses against the dock wall still hold good but take it carefully as a flying stream of solidified urine can cause offence! Every couple of years I clean the scale from my plastic holding tank by blasting it with water through the inspection hatch, combined with banging the sides with my hand.
 
Disregarding the aluminium tank for the moment, filling the hoses with hydrochloric acid is a rather inefficient way to remove the insoluble salts that build up in them. It will work eventually but it will take a lot of acid and several days. Mechanical methods are far more effective, the old advice to bang hoses against the dock wall still hold good but take it carefully as a flying stream of solidified urine can cause offence! Every couple of years I clean the scale from my plastic holding tank by blasting it with water through the inspection hatch, combined with banging the sides with my hand.
+1.

This was also the method we used for our charter fleets. Unfortunately, difficult to implement on some boats due to inaccessible or bendy pipe runs - a bad design feature anyway.

Lots of labour saved by positioning holding tanks to high level above heads bowl, and ensuring large diameter, straight run-outs from tank to (re-positioned) skin fittings. Then the exit pipe could be rodded through from the deck pump-out fitting.
 
I haven't seen the clip yet. However, you want to avoid putting pure aluminium anywhere near salt water as well as it fizzes away and dissolves quite rapidly. Fortunately, the alloys used in boat hulls are much more stable. :D

But the question was about the holding tank. It would be unwise to assume that the holding tank is made of the same alloy as the hull I think? Better safe than sorry anyway. :)
 
But the question was about the holding tank. It would be unwise to assume that the holding tank is made of the same alloy as the hull I think? Better safe than sorry anyway. :)

Yes, but I can state with certainty that it will not be made from pure aluminium. My point was that it's incorrect to compare reactivity of pure aluminium and alloys. I believe that the clip mentioned related to pure aluminium and might lead people to believe that hull & fittings would behave in the same fashion. Still haven't seen the clip though as WiFi link is slow just now.

Not suggesting use of hydrochloric acid to clean aluminium tanks, just pointing out that the corrosion rate will be very much slower (even slower if surface is anodised).
 
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Yes, but I can state with certainty that it will not be made from pure aluminium. My point was that it's incorrect to compare reactivity of pure aluminium and alloys. I believe that the clip mentioned related to pure aluminium and might lead people to believe that hull & fittings would behave in the same fashion. Still haven't seen the clip though as WiFi link is slow just now.

Not suggesting use of hydrochloric acid to clean aluminium tanks, just pointing out that the corrosion rate will be very much slower (even slower if surface is anodised).

Ok, thank you for the clarification. :)
 
Yes, but I can state with certainty that it will not be made from pure aluminium. My point was that it's incorrect to compare reactivity of pure aluminium and alloys. I believe that the clip mentioned related to pure aluminium and might lead people to believe that hull & fittings would behave in the same fashion. Still haven't seen the clip though as WiFi link is slow just now.

Not suggesting use of hydrochloric acid to clean aluminium tanks, just pointing out that the corrosion rate will be very much slower (even slower if surface is anodised).

There is no doubt that some aluminium alloys are relatively inert to attack by HCl. The photo shows 20% hydrochloric acid removing scale between a stainless steel aerial antenna and an aluminium alloy bracket. Although the scale is fizzing nicely the aluminium was not attacked.
IMG_0740_zps4d5a2e38.jpg
 
Thanks for the knowledgeable responses. I have suffered scale problems in the past both in hoses and Y valve and solved them mechanically as mentioned but not without difficulty. With more awareness I now try to prevent build-up but wondered how others maintained their waste systems.
From now on my routine will be: (1) Encourage plenty of pumping after use to flush urine through - maybe not so much at night! (2) Regular squirts of baby/olive oil to hinder 'stickability'. (3) Every couple of months dose from head via Y valve to sea valve with 'dilute' HCl as advised and bought locally. I have a piece of aluminium/alloy picked off the Alubat factory floor during Seren's build so will test that with a 24 hr immersion in said HCl. (4) Before each of the 2 planned haul outs this season in the Med. dose whole system including riser pipe/holding tank with Leesan's biodegradeable descaler LeeScale for 24 hrs and flush well.
I believe Leescale to be mainly phosphoric acid - an ingredient of Coka Cola and in the past have ben advised that regular dosing with cheap cola would do the trick.
If my experiment and further research indicate that using HCl will not be corrosive to the holding tank I may well use that throughout the system in future years. It will certainly be less expensive and easier to obtain.
 
Regular dosing with hydrochloric acid helps to prevent accumulations of salts, far more useful than trying to solve a serious blockage problem with it. Fortnightly or weekly treatment works for many liveaboards and long term users (plus almost every house in the Mediterranean countries). I use one half-litre bottle of acid as it comes, empty the bowl, tip about a third of the bottle in, pump a couple of times, wait for fizzing to stop. Repeat twice. Flush through. This seems to help with the discharge and joker valves, and maybe the hose to some extent. Using this much means that the acid will not reach your holding tank until it has been largely reacted in the toilet and riser side of the loop, so your aluminium tank should be safe, especially if you flush it all through.

I'm not sure what nylon components are in the average toilet, if any. I think the rubber used is EPDM, which gets an 'excellent' for 20% hydrochloric acid in this table http://www.quickcutgasket.com/pdf/Chemical-Resistance-Chart.pdf In years of doing this for my RM69 manual toilet and now my Jabsco LITE electric one I have seen no evidence of attack by the acid.
 
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