Drinking water pipe cleaning

[Papawads]

I pulled out our 220liter water tank">fresh water tank for keelboat work, and noticed the water inlet hose has thin black slime/residue on the inside wall - YUK.

Yes, we use water treatment.

Replacement of the hoses is a job straight from hell; Jeanneau cared little for such tasks during construction.

So.... could I pull the hose from the tank, block the end, and fill the pipe with SOMETHING? to diak in, to clear out that slime?

Maybe 24 hours in vinegar?

Yes - drained into a bucket and the pipe washed out.

Thoughts on what that something may be, to soak the pipes in? Is there a product for this?

I made the mistake of pointing out the slime to the Admiral, and now she looks at the water faucet, like she would a plague victim.

My fridge is full of water bottles, displacing my beer.

This is a crisis!?!?

Papawads

[Tin Tin]

Most people put cup full of bleach in the tank, let it flow through all the faucets and let it sit for a few hours. Then flush until chlorine smell disappears - you must get every line including deck shower etc. (Don't run it through your water-maker)
Install an in line 0.5micron carbon (or ceramic) filter in the galley cold water line if you are worried about bugs/cysts etc carbon will also remove chlorine.

[Jammer]

Tin Tin has the right idea.

Too much chlorine will attack the tank and plumbing. Not enough won't solve the problem. Since some of the chlorine is "used up" (bound) by minerals in the water, and by the crud you're trying to dissolve, it is impossible to determine the exact ratio of chlorine to water required.

I use free chlorine test strips and shoot for 10 ppm initially and around 2 ppm chlorine residual after a few hours. It is useful to open the taps so that the chlorine circulates around through all the plumbing, both upfront and every 20 minutes or so. Ideally you would put a hose on the taps so that the water can go back into the freshwater tank and just keep recirculating but I find that to be more trouble than it is worth.

I start with two tablespoons of bleach in a 38 gallon tank and adjust from there based on the test strips.


Free chlorine test strips are available from many sources: amazon, restaurant supply places, swimming pool supply places, etc.

[Turtle Blues]

Plus 1 on the chlorine and more importantly the test strips and measuring. The target is .05% total chlorine - bleach is about 3.5% so a little math is required - it does not take a lot.
After sufficient standing time (24 hours) to disinfect proper flushing is required.
Also visual inspection of the tank if possible - I have opened supposedly clean tanks to find dense organics floating. It looked like a kombucha fermenter.


Edited for the concentration - .05% is for sterilization.
As a reference chlorinated drinking water is under 4 parts per million.

[rslifkin]

In general for using bleach to sterilize a water system, higher concentrations than strictly necessarily will allow a shorter contact time with similar effect in the end.

[hjohnson]

Also note that “crud” in the hoses, while unappealing, doesn’t necessarily mean things are bad/unsanitary. I work with a small rural water system for a remote community. It passes every test required by legislation, and is far and away some of the best drinking water I have ever seen. But you do not want to see what happens each spring when we flush the water mains.

[desodave]

This is a previous thread on shocking water tanks and plumbing;
https://www.cruisersforum.com/forums...er-270833.html
There is a link to a Practical Sailor article near the end of the thread that I posted;
https://www.practical-sailor.com/blo...ted-water-tank


It says to use 1ml of unscented bleach per litre of water capacity ( 220 ml in your case), premix the bleach and some water, fill the tank with the solution in it, run it into the plumbing, leave it for 4 hours, then drain a couple of times. Use a higher concentration, and you can leave it in a shorter time. These numbers are consistent with those on Canadian public health sites that I've seen.


I was leaving the bleach solution in overnight (almost 20 hours) and the chlorine taste/smell was persisting. When I did it for the recommended 4 hours, it didn't last. The article also says to use hydrogen peroxide to eliminate the chlorine taste/small if it does persist, not vinegar ... apparently the vinegar can ferment and undo the work ! Key for you is to run the bleach solution into your plumbing until you can smell it at each tap before you leave it. Take all the filters and screens out. We also have a transom shower and you have to get the bleach solution into that part of the system as well.

[Grattaway]

inlet hose so larger than outlet?

I have before blown a length of builders line through a hose and then pulled a cleaning wad through
can be soaked in something to clean - bleach or vinegar and if you get a line through it can be done quite a few times -rinse and repeat
If it short enough run you may even get a flexible line through (galv clothes line or similar)

Get it fixed quick before the water bottles take over permanently :-( and certainly dont let anyone see what comes out :-)

[Papawads]

Originally Posted by Grattaway

inlet hose so larger than outlet?

I have before blown a length of builders line through a hose and then pulled a cleaning wad through
can be soaked in something to clean - bleach or vinegar and if you get a line through it can be done quite a few times -rinse and repeat
If it short enough run you may even get a flexible line through (galv clothes line or similar)

Get it fixed quick before the water bottles take over permanently :-( and certainly dont let anyone see what comes out :-)

Genius