Liquid Bleach - Uk

[robquick]

Hi,

In the UK it appears impossible to purchase liquid bleach greater than 4% in strength unless you buy 12% bleach in 25l containers from a pool supplier.

Would 4% supermarket bleach work ?

Has anyone found a simple method of measuring out small volumes of bleach (20ml) from a 25l container without spilling on every occasion !!!!

Cheers.

[chem geek]

It would work, but you want to make sure it's plain bleach and doesn't have thickeners in it (i.e. "splashless", "outdoor" or other specialty bleaches). It might have a lot of excess lye in it and unfortunately that would tend to make the pH rise more. You can try the 4% bleach and see what happens. I'm more concerned about what you can use as a pH buffer since borates (boric acid) isn't readily available in Europe. A phosphate buffer would work, but it precipitates calcium so can be a cloudy mess initially.

[robquick]

I guess the 12% pool bleach would be a better choice then. The size of the 25l container feels like its going to be a pain to measure such small volumes?

Any suggestions??

Thanks.

[chem geek]

You should be able to get 10 liters of 4.9% of http://www.aqua-poolsandleisure.co.uk/chlorine-liquid---sodium-hypochlorie-49---10lts---only-suitable-for-above-ground-pools-up-to-12-585-p.asp'>Crown Liquid Chlorine or 10 liters of 14-15% http://www.ebay.co.uk/itm/Liquid-Chlorine-Sodium-Hypochlorite-14-15-10Lts-/160529749649?'>liquid chlorine or http://www.easypoolchemicals.co.uk/shop/3/index.htm'>here or 5 liter of 10%/11% http://www.crystalpools.co.uk/chemicals_water_treatment.php'>here.

The main problem with the 25 liters is that the higher percentage concentration of chlorine degrades faster and you won't be using it that quickly. As for measuring, you can use a pipette or baster to remove some, but be careful not to spill as you know how it will bleach out any fabric!

[Topspeed007]

I use plain bleach from Tesco or Asda in 1 or 2 litre bottles. Tesco 2 litres is around 30p from memory so cost is next to nothing. I doubt it is 4% though, my vague calculations reason on it being nearer 3% but even so in my 1500litre spa I put 200ml in daily (using 2 step system / bromine) and no floater as my wife has an allergic reaction to bromine tabs. You can get 6% from online swimming pool retailers but doesn't make cost sense when you add P&P. hope this helps.

[robquick]

Thanks for the two replies.

Chem geek, I currently use one teaspoon of Calcium Hypochlorite daily (between soaks only), 24 hours later my FC will be around 1.5ppm ready for a potential soak. If I was to use the 14/15% bleach is it possible to calculate what the equivilant of 1 teaspoon of bleach is in ml ?

Topspeed007, how long have you used the Tesco bleach for and what are the results like ?

Thanks.

[robquick]

Chem Geek,

One other question, what strength bleach would you recommend ?

Thanks.

[chem geek]

1 teaspoon of 65% Cal-Hypo in 1325 liters (350 gallons) would give 2.5 ppm FC so assuming you are always starting out with the same chlorine level and you are mostly adding this to handle daily bather load, then that's roughly 20 minutes of one person soaking (if there is no ozonator). This amount of chlorine is equivalent to 1.8 fluid ounces (53 ml) of 6% bleach so you can scale accordingly for different bleach concentrations. The mid-range bleaches at 6-8% tend to have less excess lye in them so are usually better than the 3% variety, but the 3% aren't necessarily bad. Pool store chlorine at 10-12.5% or more is fine except it doesn't last as long in concentrated form. Up to you as to what to use -- probably mostly determined by availability.