Cleaning water tanks

MJWB

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Finally getting around to cleaning (if needed) the water tank and pipes on a new to me boat I recently bought. I've no reliable idea when it was last done and don't know what current water quality is like. There are some well old Aquaclear or such like tablets on board. Thinking of buying a water quality test kit to start with. Metal water tank, plastic pipes. Please, any advice out there? Would very much appreciate advice available. Thanks.
 

duncan99210

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I’d not over think this one. Drain the current contents, refill the system with water from a reliable source and see what it tastes like. If the water is clear from the tap and tastes OK, then you’ve got a clean water system: go sailing. If the water is discoloured or tastes weird, drain the system, refill using well diluted Milton (or similar) and repeat until you get clear water: rinse system with fresh water and check taste.
I simply drain the system each winter, leaving it empty, refill on launching and that’s it. Not had a problem in all the time I’ve had the boat (11 years now) unless I’ve managed to fill it with poor quality water.
 

Simon 420

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Bleach solution works well for us. Fill the tank with fresh water to which you add about half a bottle of the cheapest own brand bleach you can get (not the perfumed variety) and then leave for a few hours. Flush through 3-4 times. We then use the tablets if we know we're going to be leaving the tanks undisturbed for longer than a week.
We don't drink direct from the tank because we're not that keen on the taste of the water at the marina, so shuttle a dozen 2 litre water bottles to and from home for drinking. Recently had a fortnight on the boat and lasted out on 24 bottles, all stored under one of the bunks in guest cabin as near to centre line as we can get them.
Call us overcautious if you like!
 

coopec

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Finally getting around to cleaning (if needed) the water tank and pipes on a new to me boat I recently bought. I've no reliable idea when it was last done and don't know what current water quality is like. There are some well old Aquaclear or such like tablets on board. Thinking of buying a water quality test kit to start with. Metal water tank, plastic pipes. Please, any advice out there? Would very much appreciate advice available. Thanks.
Health Risks From Plastic Water Pipes | Livestrong.com
www.livestrong.com › Nutrition › Nutrition Basics › Food and Health


Since the 1950s, plastic water pipes have been the material of choice for plumbers and home builders. ... in homes built before 1977, installed PVC pipes were found to leach polyvinyl chloride into drinking water at levels above the ... Infants, in particular, do not process phthalates well. ... Clear Plastic Wrap & Food Safety. 3 ..
 

MJWB

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I’d not over think this one. Drain the current contents, refill the system with water from a reliable source and see what it tastes like. If the water is clear from the tap and tastes OK, then you’ve got a clean water system: go sailing. If the water is discoloured or tastes weird, drain the system, refill using well diluted Milton (or similar) and repeat until you get clear water: rinse system with fresh water and check taste.
I simply drain the system each winter, leaving it empty, refill on launching and that’s it. Not had a problem in all the time I’ve had the boat (11 years now) unless I’ve managed to fill it with poor quality water.
Thanks
 

MJWB

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Bleach solution works well for us. Fill the tank with fresh water to which you add about half a bottle of the cheapest own brand bleach you can get (not the perfumed variety) and then leave for a few hours. Flush through 3-4 times. We then use the tablets if we know we're going to be leaving the tanks undisturbed for longer than a week.
We don't drink direct from the tank because we're not that keen on the taste of the water at the marina, so shuttle a dozen 2 litre water bottles to and from home for drinking. Recently had a fortnight on the boat and lasted out on 24 bottles, all stored under one of the bunks in guest cabin as near to centre line as we can get them.
Call us overcautious if you like!
Thanks
 

pvb

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Finally getting around to cleaning (if needed) the water tank and pipes on a new to me boat I recently bought. I've no reliable idea when it was last done and don't know what current water quality is like. There are some well old Aquaclear or such like tablets on board. Thinking of buying a water quality test kit to start with. Metal water tank, plastic pipes. Please, any advice out there? Would very much appreciate advice available. Thanks.

Once you've cleaned the system (and cheap bleach works fine and is safe), it's worth dosing the tank with purification tablets every time you fill it, to keep bugs at bay. I use AquaTabs Midi Tabs, they seem to be effective.

Almost all PVC piping sold for boat use is food grade, so you can safely ignore the scaremongering about PVC pipe.
 

Rafiki

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Finally getting around to cleaning (if needed) the water tank and pipes on a new to me boat I recently bought. I've no reliable idea when it was last done and don't know what current water quality is like. There are some well old Aquaclear or such like tablets on board. Thinking of buying a water quality test kit to start with. Metal water tank, plastic pipes. Please, any advice out there? Would very much appreciate advice available. Thanks.
Tesco thin Bleach 38pence, mix about 3% by volume, make sure it has been pulled to all parts of the system ie the taps , leave for 3 or 4 hours then drain and rinse twice. If not satisfied repeat and leave in the system for longer.
I do this every spring, it's easier and cheaper than using a filter.
If you are very fussy buy bottled water for drinks and use the ship's tanks for washing up, washing self, cooking and hot drinks.
 

ashtead

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If you want a smaller bottle and have budget buy Milton or the Wilco equivalent etc and add half from time to time. Best thing is to fit a Jabsco filter to the galley tap . I’m assuming the water you put in is ok and you don’t want to invest in a filter on the filler line before it reaches the boat tank. That said for drinking purposes bottles of water from Lidl work well and can be stored in fridge or chiller box and then decanted into each crew members named water bottle of choice.
 

Momac

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I did use Milton , or the equivalent cheaper version, when I bought my boat since I know it had been unused a while before I bought it.
But in recent years I don't use any chemicals other than tap water .
The system is left a s empty as possible over winter and receives a good flush with fresh water in the spring. We are adding water weekly if not more often at this time of year . As with many things on boat it is the lack of use that leads to concerns and issues.
We use a couple of 5 litre water bottles for drinking water - bought fresh each year as supermarket spring water and refilling them from a mains supply.
The marina pontoon water this time of year can be very warm if no one has drawn from it for a few hours so let it run cold before adding it to the tank , also flush the hose through.
 

dulls

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I did use Milton , or the equivalent cheaper version, when I bought my boat since I know it had been unused a while before I bought it.
But in recent years I don't use any chemicals other than tap water .
The system is left a s empty as possible over winter and receives a good flush with fresh water in the spring. We are adding water weekly if not more often at this time of year . As with many things on boat it is the lack of use that leads to concerns and issues.
We use a couple of 5 litre water bottles for drinking water - bought fresh each year as supermarket spring water and refilling them from a mains supply.
The marina pontoon water this time of year can be very warm if no one has drawn from it for a few hours so let it run cold before adding it to the tank , also flush the hose through.
You raise an interesting issue. Is it best to empty if leaving for a while or leave full?
 

Momac

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You raise an interesting issue. Is it best to empty if leaving for a while or leave full?
Given the choice - leave empty . And if left for along while let the taps run while filling the tank to rinse out the pipes .
 

NotBirdseye

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Not necessarily true. When you're going to not use a water tank for a long period not only should you empty it, but you should dry it out. There are a couple of methods to do this. Then it's a case of a quick wash when you want to use it next. Leaving the water in the tank in a potentially warm, wet environment bacteria thrive and it can be a touch more challenging to clean depending on how the bacteria has spread. Even if you've reduced the water content by 98% you've reduced the area that bacteria can use.

And it means that you won't be tempted to drink it...
 
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