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Ross

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Having moved out onto acreage I now only have tank water, which is collected off a tin roof.

Does anyone know the typical water profile I'm likely to be getting, or are there too many variables??...
 
G'day Ross
Take some water to a swimming pool chemical supplier, and have it tested

Normell
 
normell said:
G'day Ross
Take some water to a swimming pool chemical supplier, and have it tested

Normell
[post="50954"][/post]​


Norm,

Are they able/willing to give a full chemical analysis? I thought they were limited to basis ph levels etc, which are easy to do yourself?
 
Yeah, don't know Ross
Maybe take some to Brisbane Water ?????
 
Hi Ross

If you dont live right on the coast, and the tank is lined (or at least isnt leaching concrete into the water) then I would expect the short answer is there is bugger all in your water in terms of major ions (being sodium, calcium, magnesium, chloride, sulphate, carbonate, bicarbonate). You will probably have some minor organic compounds from leaves and the odd dead possum, and maybe some coliforms if the possum crapped in there before he died. The cheapest test would be to measure the electric conductivity which would give a good idea of how many ions in total are in the water. Not sure if swimming pool shops do that or not.

So, the chances are the water is defficient in the ions you want for AG brewing and if it was me I would be adding salts, working out the amount by assuming the tank water concentrations are zero. And personally I would do all my water additions to the brew pre-boil, no top up after, just to get rid of any coliforms.

But I'm sure some tank brewers will have better advice from experience.
 
GL,

You just confirmed my views on it :D . I've made up a "salt cocktail" which I add pre boil - Used to collect my water from the HBS before I went AG as worried what might be lurking....
 
Ross

I use rain water for a lot of my beers as Adelaide water ain't the best. I just add some Calcium Chloride for the lighter styles like pils and add gypsum for the darker beers where I need to bring out the bitterness more like Pale Ales.


If you use Promash(tm) or one of those other brewing programs :p, use 0 for all of the values of salts in your water and just add salts as you need to get your the water profile you want. Aim for at least 50ppm of Calcium to keep the yeasties happy. Remember, close enough is good enough with your calculations.

Cheers
Pedro
 
Thanks Ross
A interesting thread and one I will be watching closely as I will be a tank water brewer in the near future.
I am sure POL could add something to this , I believe she also uses tank water.
Not going to filter it Ross? :lol:

Batz
 
seems like a lot of messing around why not get some spare plastic containers and go to nearest friends place a few days before you brew and get some tap water
cheers
fergi
 
It comes out of a tap :lol:
 
Not sure how representative this is but the rainwater from my corrugated iron tank has a pH of 8.

Jovial Monk
 
Jovial_Monk said:
Not sure how representative this is but the rainwater from my corrugated iron tank has a pH of 8.

Jovial Monk
[post="51038"][/post]​


JM,


Mine is 6.9.

They will vary comparative to the catchment surface.

Steve
 
& how much bat/pidgeon poop it collects..... :)
 
The water from my tank is close to 8.0 as well at the moment.
It comes down a bit after it rains and the tank fills up.
It only holds 1000 galls (imp) or 4500 litrs approx.
Cheers
 
& how much bat/pidgeon poop it collects..... :)


Well this is pretty much what super-phosphate is!

In general rain collected in urban areas will be slightly acidic (pH <7) due to acid rain caused by industrial pollution.
CO2 is released into the atmosphere by combustion engined vehicles and industry where it reacts with water in the atmosphere to form carbonic acid (HCO3) at the cloud level. Then the rain is slightly acidic.

I suppose that carbonate ions are present in the rain and over time the pH may increase due to other factors (i cant think of any off the top of my head, but possible H2 being released?) leaving carbonate as the predominate ion in solution. Carbonate being the conjugate base will increase the pH of the water.
 
Ross said:
& how much bat/pidgeon poop it collects..... :)
[post="51049"][/post]​

hope your not planning any roof partys batz. :D :lol:

cheers
big d
 
Hahaha big d,
I just checked the PH of the water in my tank and it is 7.9.
Dropped it to 5.5 by adding 4mls of pure phosphoric acid ( not the cleaning stuff) in 41 litres.
I am planning a pilsner tomorrow if the WL 800 starter kicks in.

Cheers
 
actually dicko im with you and batz on this one .it is a very interseting topic as i too will be relying on rainwater only when i move down south.ive written down pedros info and will visit my chemist mate at work tonight to see if they stock calcium chloride.scored some lab grade gypsum last night.
never have bothered much with water profiles but i reckon i may as well start taking an interest in it now so im better prepared down the track.

cheers
big d
 
Big d,
Chiller and Pedro have given me a good insight into water adjustments.
I use the ordinary supply for English/ Aussie ales but I am now using rain water for most other styles and adjusting it to suit as per Chillers instructions.
Just getting used to it all at the moment.
Cheers
 
My tank water is pH 6.2.

I suspect that this is related to the fact that my local soil is acidic, therefore any dust floating around will affect the pH. Also, becaue of the minimal amounts of dissolved minerals, the solution is almost unbuffered. Our water catchment has a first flush diverter to divert the first rinse of rainwater from the tanks.

I use promash, assume that all minerals are 0, then back off the resulting mineralization by 10%.

For any kit brewer using rainwater, do not worry about mineral additions, as most of the needed addtions are done at mashing. Your wort is dehydrated and needs no extra minerals added to it. Remember to boil all your brew water and use within a day or two of boiling. Then airate well as the boiling removes dissolved O2.
 
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