Tank cleaning - Where has all the thin bleach gone?

[pmcdermott]

I give my water tank an annual clean by adding the right quantity of clear thin bleach into a full tank and leaving it overnight before flushing. Tescos Value Clear Thin Bleach for about 38p was my go-to bleach. It was difficult to find last year in the middle of the Coronavirus panic, but I found some in the end. Now it seems to have disappeared completely. Anyone know where I can buy clear thin bleach? (preferably not online, as the shipping makes no sense for such a cheap product).

I know there are various tank cleaning products available in Chandleries etc., but none of them can beat the 38p price point.

 

[pvb]

Asda do it - Online Food Shopping | Grocery Delivery | ASDA Groceries

 

[Gary Fox]

Sainsburys, lemon flavour or 'original'.

 

[pvb]

Sainsburys, lemon flavour or 'original'.

The Sainsbury's Original has perfume in it.

 

[sarabande]

My bleach is too thick, dear Henry, dear Henry, my bleach is too thick.

Add water, dear Lisa, dear Lisa, add water.

 

[Fantasie 19]

Chuck a handful of Milton tablets in there?

 

[Bilgediver]

Chuck a handful of Milton tablets in there?

Don't need that many, Have to settle for Milton liquid but do do a double dose in the spring. It does not put a taste in the water. I also add a wee dose from time to time during the season.

 

[TernVI]

My bleach is too thick, dear Henry, dear Henry, my bleach is too thick.

Add water, dear Lisa, dear Lisa, add water.

Thick bleach often contains caustic soda as well as hypochlorite.

 

[madabouttheboat]

Where has all the thin bleach gone and where are all the gods?
Where's the streetwise Hercules to fight the rising odds?
Isn't there a white knight upon a fiery steed?
Late at night I toss and I turn, and I dream of what I need


I'll just leave that with you to hum for the rest of the afternoon (well you started it)

 

[MoodySabre]

I use baby steriliser stuff from a Pound shop.

 

[penfold]

I'd be surprised if Didldidi don't have own-brand strong bleach.

 

[pvb]

I'd be surprised if Didldidi don't have own-brand strong bleach.

Aldi's bleach also contains sodium hydroxide and perfume. Not the stuff to use in a water tank.

 

[Sailingsaves]

And if not milton (the baby steriliser stuff; or stuff that sterilises drinking cups etc for babies rather than sterilises babies )

milton - Google Shopping

How about sterilising tablets from a caravan supply shop?

 

[pvb]

I've only once cleaned out a water tank with bleach. It was when I bought a 5 year old Hallberg-Rassy which had spent its time in Spain. The underfloor GRP tank had big inspection hatches, and I was able to get my hand inside and brush the rubbish off the inside. After lots of rinsing, I then filled it with a bleach solution to soak for a while.

Since then, I just add water purification tablets every time I fill the tank. I use AquaTabs Midi tablets. I don't drain the tanks in winter.

 

[Norman_E]

Do not use chlorine bleach in stainless steel tanks. It encourages corrosion of the welds, leading to pinhole leaks.

 

[Momac]

I just use tap water flushed thorough the tank and pipes annually and used regularly in between. It is cheaper than 38p = no extra charge at the marina , but guess that depends which country you are in and whether you moor your boat near a tap .

 

[ip485]

Dont use the nasty slimey super market stuff with all sorts of additives. If you go along to a hot tub / pool shop you can buy bleach granules - shock chlorine granules. They will do the job perfectly. Mix with some water to achieve the solution you wish and away you go.

As someone else said, bleach and aluminium is not a good combination. I reckon if it is well flushed through it is fine, but dont leave it in contact.

More often than not the problems are not in the tank but the pipes, especially if they are flexible. They encourage the growth of various slime moulds and bacteria. You can flush some chlorine solution just through the pipes without putting it in the tank, and may be pleasantly surprised how fresh it keeps the water for a few months.

Pool shock is cheap and a small tub of granules will last you a very long time. Any pool shop will sell you a tub.

Oh one other tip, mix it with some warm water, let it settle as you will find some sediment. Poor off the liquid and leave the sediment behind. This way you dont introduce any particles into the tanks or pipes, although I expect they dissolve quickly.

There have been a lot fo studies that at low concentrations (look it up) it is safe in potable water as well, so you can maintain a very low level in the tanks to keep the water fresh and pure, but I am not sure I would even then if your tanks are aluminium and I am not sure it is necessary either once they have had a good flush through, repeated a few times a year if necessary.

 

[LittleSister]

I also add a wee dose from time to time during the season.

?

 

[thinwater]

You all realize of course that...

a) You are only adding 25 ppm (350 ppm of solution) bleach to the water for shock cleaning. Hardly any.
b) You will rinse it out.

The surfactant that adds thickness (to prevent nuisance splashing) might actually help with cleaning.

But yeah, I'd use the plain stuff.

---

If you want something that is less corrosive to aluminum, use dichloroisocyanurinate. ~ 20x less damaging.

 

[pvb]

If you want something that is less corrosive to aluminum, use dichloroisocyanurinate. ~ 20x less damaging.

... which is the active ingredient in AquaTabs.