Cryptosporidium how to clean water tanks?

[C08]

I filled my water tanks in the area currently affected by the infestation in the Brixham/Kingswear area. No ill effects so far but all water was boiled so the tanks may be affected or not. I have a couple of Aquasource water filters but no info on filtration micron size. Any recommendations on cleaning/safeguarding my water tanks. From what I read Aqua Tabs etc do not work on parasites?

 

[chris-s]

Chlorine? You can dose it heavily and then remove it, but I don’t know the details.

 

[Trident]

To protect yourself you need a 1 micron filter - so a ceramic like Seagull etc - the aqua source will do nothing

Hydrogen peroxide bleach will kill it (or chlorine bleach) - so you can bleach your tank water and leave for a couple of days (about 5% bleach is good) then empty and refill a couple of time with clean water

 

[smert]

A friend who is a public health chemist (at a different water company) says "1 micron filter, changed regularly. There is no Chemical option. UV treatment is possible but very technical."

He suggests emptying and flushing the system a couple of times with clean water. Or boil it. Also to speak to South West Water for advice.

 

[thinwater]

10-20 ppm chlorine for 24 hours is recommend for pools (without stabilizer, typically isocyanuric acid or a compound, which bleach does not have but I believe Aquatabs do). That is way too much to drink. However, that is only about 1 ounce of household bleach (6% hypochlorite) in a 20 gallon tank. A few ounces would be safe. Also, run it through all of the taps several times, and let that sit as well.

 

[thinwater]

A friend who is a public health chemist (at a different water company) says "1 micron filter, changed regularly. There is no Chemical option. UV treatment is possible but very technical."

He suggests emptying and flushing the system a couple of times with clean water. Or boil it. Also to speak to South West Water for advice.

Yes, but tanks can be hard to clean in the corners.

The conventional wisdom, which he implies, is that a few cysts are not a risk to a healthy person. Flushing is enough to lower the number.

Dalton and others make sub-micron filters.

 

[Refueler]

I have a box of Military tablets used to purify river water ... 1 tablet for 20litres .... dissolve - leave for 15mins ... can then drink or make tea ... tastes a bit though !!

I use them to dose my boat tanks ... dissolve tablets in 5ltr container ... 1/2 fill water tank - empty solution in - top up tank to full. Leave for a day or so - then pump out via the domestic system - so that pipes and taps get treated ....

Refill with fresh water.

Job done.

 

[Laysula]

Before you go to the trouble of cleaning tanks out see if you can get it tested first. Have a word with Martyn at the office he may well have a bit more clout than an individual regarding this.I also think that it's just higher Brixham which has been affected but sww are taking no chances.

 

[thinwater]

Before you go to the trouble of cleaning tanks out see if you can get it tested first. Have a word with Martyn at the office he may well have a bit more clout than an individual regarding this.I also think that it's just higher Brixham which has been affected but sww are taking no chances.

Boats are different from houses, so cleaning and sanitizing the tanks is just good hygiene. Unlike you house, they are not continuously chlorinated. Thus, cleaning and sanitizing tanks is a part of any good spring commissioning process. In my case, I clean them and get them bone dry before winter so that nothing can grow. The lines are anti-freezed, which sanitizes them, if done properly.

All I need to do in the spring is fill the tank and use that to flush the lines. Then pop in a new 0.5 micron carbon block filter. Clean, fresh water all season.

 

[lustyd]

It’s resistant to chlorine and bleach so probably worth doing some proper research.

 

[ylop]

Before you go to the trouble of cleaning tanks out see if you can get it tested first. Have a word with Martyn at the office he may well have a bit more clout than an individual regarding this.I also think that it's just higher Brixham which has been affected but sww are taking no chances.

Testing is really expensive, and will only tell you about the particular part of the tank you sample (hard to mix a tank).

They don’t grow easily in a water system so draining and refilling should massively reduce the problem. Draining, flushing through once and refilling almost certainly enough. Nobody is going to be visiting every house to treat their pipe work so rely on simply flushing through there.

 

[C08]

To protect yourself you need a 1 micron filter - so a ceramic like Seagull etc - the aqua source will do nothing

Hydrogen peroxide bleach will kill it (or chlorine bleach) - so you can bleach your tank water and leave for a couple of days (about 5% bleach is good) then empty and refill a couple of time with clean water

Thanks for you thoughts but 5% bleach would be 1 gallon for a 20 gallon tank-sounds a lot?

 

[oldbloke]

Crypto sporidium literally hidden spores. Very small so difficult to filter ( and find under microsope) and spores so very tough and difficult to kill. Fortunately for the average healthy(ish) person it is a nuisance rather than serious. It wasn't recognised , or looked for, as a common waterborne infection u til the early 80s. Difficult to know if it wasn't an issue till then or just not looked for.
I would think flushing the tank thoroughly is the route to take, sensible levels of chlorine won't help, hence the problem in Brixham

 

[C08]

On refllection cleaning out a boat tank system is a very different problem to the water board pipework where it is not possible to effectively decontaminate pipes without detriment to the water quality. I think a tank flush out to shift the bulk of contamnent tand refill then treatment of the water, flush out a couple of times and then a new 1 micron filet fitted-and hope for the best!. Thanks for ideas.

 

[Thistle]

Also to speak to South West Water for advice.

... and their address for you to send the bill.

 

[Trident]

Thanks for you thoughts but 5% bleach would be 1 gallon for a 20 gallon tank-sounds a lot?

Yes its hard to kill - you can go 3% on hydrogen peroxide but still a lot - my tanks are 900L so an even bigger problem but swimming pool powdered chlorine will need considerably less than liquid bleach

In my case the Seagull filter protects from all so I'll just empty and fill the tanks a few times next time I get to a good supply and not worry much more than that.

 

[lustyd]

swimming pool powdered chlorine

It’s chlorine resistant though, that’s the problem!

 

[Trident]

It’s chlorine resistant though, that’s the problem!

Yes but over 5% will kill it - so it just needs an awful lot - no good for drinking but cleaning out tanks it doesn't matter

 

[ylop]

Yes but over 5% will kill it - so it just needs an awful lot - no good for drinking but cleaning out tanks it doesn't matter

Where are you going to discharge your several hundred litres of 5% hypochlorite? Whilst I appreciate that in the whole ocean it’s tiny quantity - we would all criticise any commercial operation that dirched

 

[MontyMariner]

Out of interest, on a steel tank and difficult to achieve, but would a steam clean do the job?