f/w tank cleaning - again :)

[tomdmx]

Hi All,
I read the posts about tank cleaning but wanted to verify what I want to do..I've a 140l plastic f/w tank which sits in the bilge. The tank was left empty for at least a year and after recent grit blasting particles went into the tank..
So I removed the tank, flushed out with hose as much as I could (a number of fills and tips then hose downs etc) and was going to use a bleech (at a ratio of half liter for full tank?) and flush it out then white vinegar (at a ration of 6l for the tank), leaving it for a few days then proper flush out...

Would that do the job or do I need to do something else (or do it another way)?

 

[nigelmercier]

A bit OTT; did the grit have HIV infected blood on it or something? Just fill it up, and put a couple of Milton tablets in.

 

[VicS]

A bit OTT; did the grit have HIV infected blood on it or something? Just fill it up, and put a couple of Milton tablets in.

A bit OTT but not by all that much, although maybe not necessary

For sterilising water tanks Milton recommend 30ml per 5 litres. ( 6 ml per litre)
In a 140 litre tank that would work out at 840 ml. The concentration of hypochlorite in bleach is typically 2.5 times its concentration in Milton so the appropriate volume of bleach to use would be around 300 to 350ml

However if the tank has been well cleaned and not in need of sterilisation all that is required is to dose the water with Milton at the rate of 2.5mls per 5 litres, ie 70 mls in the full 140 litres, and allow it to stand for at least 15 minutes before use.

 

[EdWingfield]

Even cheaper is to get sterilising tablets from Home Bargains and follow the instructions.

It's essential you know the volume of tank and whether you are sterilising to begin with or dosing thereafter.

If you are unsure of time/concentration you can call any company through the number given on the packaging. They will connect you to a helpful guy in a white coat who will talk you through it.

Taste test at the finish. Just a drop. It should be like tap water. If it tastes like a swimming pool you've goofed.

 

[ukmctc]

a cap full of milton on every 3rd or 4th fill will be more than enough, and clean your filter out as required.

 

[vyv_cox]

We recently bought a boat with flexible bag type water tanks. They had been neglected for years, were completely lined with black deposits and looked most unpleasant for containing anything we might drink. We were on the point of ordering new ones but decided to have a go at cleaning them first. With only pieces of rag tied to the end of a stick the difference was astonishing, they came up perfectly clean. A brief dose of Milton has sorted them out completely, which also helps the hoses, although ours were all replaced.

On our Sadler I periodically brush out the tank via the inspection hatches, then Milton. This did nothing for the taste until I replaced the hoses, which transformed drinking water quality.

 

[tomdmx]

There is some black deposits and I can get to some of it through the inspection hole but not all as its partitioned so difficult to wash all off..

Anyway cleaned as much as I can and will use Milton to sort the rest, thank you all for great info as always

 

[nigelmercier]

My suggestion of a couple of Milton tablets was not to sterilise the tank, as it has already been cleaned, but to maintain a low level of chlorine in the water such that it is still OK to drink.

 

[Ex-SolentBoy]

Then install a Seagull water filter and you will love the taste of the water as well.