Drinking Water from watertanks

[motion30]

That article is weak and does not provide the pertinent information. At what level is considered pure water. I doubt anything from our watermaker would reach this level

[sailorboy1]

Originally Posted by Mike OReilly

This comes from the queen of yacht sanitation systems. It has worked for us so far, but I’m not a chemist, so can’t say whether a lesser amount would be as effective.

Of course it worked. It's like using a nuclear bomb when all you needed was a BB gun.

[ben2go]

Originally Posted by motion30

That article is weak and does not provide the pertinent information. At what level is considered pure water. I doubt anything from our watermaker would reach this level

True. By pure they mean absolutely no impurities. There are a few science labs around the world that house 100% pure water for research purposes. I don't think any of us will ever achive that level without some serious equipment not for use on rec boats.




https://www.businessinsider.com/supe...autiful-2018-6

[Mike OReilly]

Originally Posted by sailorboy1

Of course it worked. It's like using a nuclear bomb when all you needed was a BB gun.

So, what’s your ratio for shocking? I’m not here to defend or insult. I’m just sharing information.

[sailorboy1]

Originally Posted by Mike OReilly

So, what’s your ratio for shocking? I’m not here to defend or insult. I’m just sharing information.

2 tablespoons (1 oz) should give a free chlorine of 4-6 ppm in 100 gals of water

With that said, there isn't anyway really to calculate the dose because bleach gets weaker with age and you don't know the chlorine demand of the growth in the tank at the start. So you have to make some assumptions (based on science not voodoo myths)

But my God, compare 2 tablespoons (1 oz) in 100 gallons to 1 cup (8 oz) in 10 gals . I bet after you drain and flush that tank 3 times it STILL has a very high free chlorine level.

[Juho]

We have tap water in the tanks, and same water in smaller bottles/containers. Both are ok, but usually we use the smaller bottles for drinking, coffee, tea etc (since water stays longer in the tanks, and the tanks are not cleaned as often).

[desodave]

Here's a reference to Practical Sailor - they say 1/8 of a cup per ten gallons for shocking.

https://www.practical-sailor.com/blo...k-11717-1.html

[a64pilot]

Originally Posted by desodave

Here's a reference to Practical Sailor - they say 1/8 of a cup per ten gallons for shocking.

https://www.practical-sailor.com/blo...k-11717-1.html

Sure, but it is like using a sledge hammer to swat flies, yes, the fly is dead, but it’s hard on the furniture.
Or in my case the aluminum tanks.
Now if you really could put that super high concentration of chlorine into a tank and flush it ALL out in a couple of hours, the the tank damage would be minimized, but you can’t flush it all out, and therefore there will be damage, plus if you do some research you will find that disinfection of water with chlorine isn’t as harmless as we have been led to believe. However it is better than the multitude of water borne illnesses that it prevents in municipal water supplies.
They however treat to 1PPM, not hundreds of PPM.

However telling someone to use that high a concentration of bleach will most assuredly kill any nasties, you won’t hear complaints that it didn’t work.

[a64pilot]

Sailorboy,
If you wouldn’t mind, it may help if you stated your background and why it is that you have an opinion on water disinfection.
If you don’t want to due to privacy, I certainly understand, and apologize for bringing it up.
However as an example my background as a pilot doesn’t mean much does it when we are discussing water disinfection.

[Mike OReilly]

Originally Posted by sailorboy1

2 tablespoons (1 oz) should give a free chlorine of 4-6 ppm in 100 gals of water



With that said, there isn't anyway really to calculate the dose because bleach gets weaker with age and you don't know the chlorine demand of the growth in the tank at the start. So you have to make some assumptions (based on science not voodoo myths)



But my God, compare 2 tablespoons (1 oz) in 100 gallons to 1 cup (8 oz) in 10 gals . I bet after you drain and flush that tank 3 times it STILL has a very high free chlorine level.

Thank you. I'm no expert on this (or anything really). I've followed the advice of those who seem to be. So I appreciate your expertise on this.

Yes, it does take a few flushings to clear the odour. Although, as I say, the greater smell/taste problem is always the antifreeze.

[Cheechako]

I do think a charcoal filter makes tank water taste a lot better. Often I think it's not bacteria etc that makes the taste bad, so UV or etc may not help. But with charcoal you definitely have to change the filter every couple of months, and that can be a pain if you are cruising the world keeping inventory.
I love RO water for some reason. Having a small tank just for drinking if you had an RO system would be nice.

[sailorboy1]

Originally Posted by a64pilot

Sailorboy,
If you wouldn’t mind, it may help if you stated your background and why it is that you have an opinion on water disinfection.

I have a "few" years experience in water treatment. But I don't want to imply I've an "expert". Other than the waste of time and water there isn't anything wrong with using super high chlorine/bleach doses as long as you flush it back down to a safe level in a reasonable amount of time. If do want to use the nuclear bomb approach do go to a pool supply place of hardware store and invest in a cheap free chlorine measuring kit. In fact it is worth having a test kit regardless if you are enough of a worry wart that you even consider the nuclear option.

I will say that from measurements back where I had my full test kit available that 1 cap of bleach into my 50-gal water tank was more than enough to treat a standard in use water tank not experiencing a "problem".

[sailorboy1]

BTW since I've a topic posting mood

For those in the cold laying up your tanks/systems with anti freeze in the winter:

There is always going to be "some" left in the tanks after you recommission them. This is the time to be adding some extra bleach. Antifreeze below a certain level becomes bio food.

[Cheechako]

I have water storage tanks at home. 1 cup bleach in 500 gallon tank is way too much. You can even smell it taking a shower.

[Exile]

Originally Posted by a64pilot

Sure, but it is like using a sledge hammer to swat flies, yes, the fly is dead, but it’s hard on the furniture.
Or in my case the aluminum tanks.
Now if you really could put that super high concentration of chlorine into a tank and flush it ALL out in a couple of hours, the the tank damage would be minimized, but you can’t flush it all out, and therefore there will be damage, plus if you do some research you will find that disinfection of water with chlorine isn’t as harmless as we have been led to believe. However it is better than the multitude of water borne illnesses that it prevents in municipal water supplies.
They however treat to 1PPM, not hundreds of PPM.

However telling someone to use that high a concentration of bleach will most assuredly kill any nasties, you won’t hear complaints that it didn’t work.

I believe chlorine also attacks stainless steel. But like in most things I'm sure, it's probably all about concentration.