# 1/2 Rainwater 1/2 Tap



## jimmyjack (2/2/07)

I have just installed a rainwater tank and am tempted to brew with some rain water. I also would like to know the CA and MG figures to calculate my residual Alaklinity for any salt additions. If I were to mix 1/2 Brisbane tap water and 1/2 rainwater to lower alkalinity and soften it a bit would I divide it in half to get an accurate water analysis. For instance if I knew that the tap water contained 20 ppm calcium would I now have 10 ppm? Have I complicated this?

Cheers, JJ


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## hockadays (2/2/07)

JJ,

From what I understand you are correct. I think half rain and brissy tap water would be good.

hockers


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## DJR (2/2/07)

Just make sure your tank water is sterile/sanitised - boil it, treat it or use a UV steriliser inline to make sure.


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## Crazy (3/2/07)

DJR said:


> Just make sure your tank water is sterile/sanitised - boil it, treat it or use a UV steriliser inline to make sure.



DJR

This is not realy required for all grain.

JJ

I have just installed my tanks as well and hope to try an all rain water brew day next weekend. I have already tested the ph and it is about 6 ish.

If you were a little persuasive you may even be able to get the people in the lab at work to give you an analysis of your water.

Derrick


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## Jye (3/2/07)

Derrick said:


> If you were a little persuasive you may even be able to get the people in the lab at work to give you an analysis of your water.



For those of us who dont have access to a lab is there anywhere we could send water to for analysis? Brisbane council put out a water report but what about brewers who cant get one.

I know in the US they have Ward Labs and it only cost them $15 for a water report.


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## jimmyjack (3/2/07)

> If you were a little persuasive you may even be able to get the people in the lab at work to give you an analysis of your water.



I never thought of that. That is a sensational idea!! 

Cheers, JJ


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## Crazy (3/2/07)

Jye said:


> For those of us who dont have access to a lab is there anywhere we could send water to for analysis? Brisbane council put out a water report but what about brewers who cant get one.
> 
> I know in the US they have Ward Labs and it only cost them $15 for a water report.



Jye

You could ask around at the Uni. There would have to be someone testing water at some stage and they may even appricate another (unknown) sample.

I belive most councils offer the service for people drinking tank water, for a fee.

Derrick


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## winkle (3/2/07)

I have just installed my tanks as well and hope to try an all rain water brew day next weekend. I have already tested the ph and it is about 6 ish.

If you were a little persuasive you may even be able to get the people in the lab at work to give you an analysis of your water.

Derrick
[/quote]

Hmmm, mine is 5.5ish. I must have more birds crapping on my roof  
Testing the water would be good though.


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## tangent (3/2/07)

rain water is generally fairly neutral compared with hard city water. (great for lager style beers, but not hard enough for a decent ale IMO)
mixing would be a good way to soften your mains water, or use 100% rain water and add gypsum to your required level.


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## jimmy01 (3/2/07)

I too have installed a rain tank recently. Seems to be a popular addition in Brissie at present! 

I'm a bit wary of using the water though without a filter. I have thought about installing a filter but it seems that to get a decent result you need to install a dual stage filter which is exxie. The other problem as I understand it, is that these filters need to be used daily to maintain hygiene of the cartridges.

Any thoughts or advice?

Cheers


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## tangent (3/2/07)

it's already gone through evaporation and precipitation, and running into a new clean tank, then you're going to boil it. Why do you need to run it through a filter?


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## jimmy01 (3/2/07)

tangent said:


> it's already gone through evaporation and precipitation, and running into a new clean tank, then you're going to boil it. Why do you need to run it through a filter?



Because of all the crap on the roof. Who knows what lands on your roof in the city.


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## tangent (3/2/07)

go have a look the next time your local council digs up the local water pipes.
my roof is damn clean compared with them.


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## MHB (3/2/07)

As an Ex-plumber who has had occasion to swim around in peoples rain water tanks, I would be wary of the water. 

Just a couple of things that come to mind, other than the self evident one about bird poop, and tanks being some form of heaven for green tree frogs:-
If the water was pure the pH would be 7, by definition.
There are still plenty of leaded cars out there; Tetraethyl lead is bad shit ok.
The most Carcinogenic compound known can be found in diesel exhaust.
Urban particulate fallout includes all the crap we love breathing including, but not limited to the above, powdered concrete, paint particles, metals, oxides of nitrogen, some very strange sulphur compounds and more.

Ok we leave the bacteria count alone as yes we are going to boil the wort - there are still lots of reasons to be careful, at a minimum I would carbon filter the water, ideally particulate filter, carbon filter then boil.

Honestly in most cases I dont think you will have any problem, just think about where you live, and what's in the air, there are places where you can get reports on atmospheric pollution (this is what will be in your water tank). Baring that find a tank thats been in use for a couple of years, make up a long dipper and see how much muck you can dredge up from the bottom.

It would be brash to blithely assume the water is OK.

MHB


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## tangent (3/2/07)

if we're going down that path, lets look at the water coles sprays their veges with and where our fruit and veg is grown
all i'm saying is there's a point when you're worrying about if you should filter your rainwater, then sucking exhaust fumes for an hour each day and smoke a pack of cigges.
let's not start the "is it ok to eat fish but not red meat" fine line debate again.

i still think rainwater would be a better lesser threat to sucking on bus diesel fumes


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## yardy (3/2/07)

tangent said:


> * use 100% rain water and add gypsum to your required level.*



off topic slightly, I brew with Rain Water, where would i find some Gypsum ?

cheers

yard


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## SpillsMostOfIt (4/2/07)

yardy said:


> off topic slightly, I brew with Rain Water, where would i find some Gypsum ?
> 
> cheers
> 
> yard



Some gardeners use gypsum to break down clay, but that is probably not food or beer grade. Come to think of it, I've never thought about Food Grade Gypsum... Is there another way?


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## tangent (4/2/07)

i looked under chemicals in the yellow pages
local(ish) place and bought 5kgs - smallest amount they sell.
plenty for later

after sept 11, they're a bit cagey though.


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## BrissyBrew (4/2/07)

As an aside I was at Ross' place the other day and had an opportunity to try a few of his house beer (always some minor modification, but somewhat stock) which had been brewed since he filled his take up with with tanker water, probably from from Brisbane City water supplies. I noticed across a few beers brewed with the new more town than tank water and they were not as soft/silky as Ross' normal brews. If you can obtain a nice soft source of water it might save you using a RO filter to get your larger water softer. But I guess it was a very non scientific and subjective evaluation.

Jimmy Jack do you have a couple flushes (sorry the technical name escapes me at present) for downfall water before it starts to top your tank. That is the first amount of rain goes down the drain whilst most of the dust and crap from your roof is being washed off by rain.


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## yardy (4/2/07)

tangent said:


> i looked under chemicals in the yellow pages
> local(ish) place and bought 5kgs - smallest amount they sell.
> plenty for later
> 
> after sept 11, they're a bit cagey though.




Thanks Tangent, out of interest, what type of shop was it, eg; garden supplies etc...

cheers


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## tangent (4/2/07)

chemical supplies
just sell chemicals


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## yardy (4/2/07)

Cheers.

Apologies for the hijack JJ.

yard


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## Batz (4/2/07)

Filter my rain water?
You have to be kidding,it wonderful fresh water,way better than any stinky old town water.

Batz


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## tangent (4/2/07)

couldn't agree more Batz :beer: 

for the SA brewers, here's where I got my food grade gypsum:
http://www.acechem.com.au/ Mooringie Avenue Camden Park (just off Marion Rd)
The bloke I talked to there is a home brewer.
Smallest amount is about $30 but it should last me up until 2025


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## Guest Lurker (4/2/07)

MHB said:


> If the water was pure the pH would be 7, by definition.
> 
> MHB



Nope. pH of water says nothing about purity. Water with nothing in it only has a pH of 7 immediately after it comes out of the distillation thingy that made it. As it sits open to the atmosphere, it absorbs CO2 and generates enough carbonic acid to have a pH significantly lower than 7. But even if your tank water has a pH of 8 (cos of cement or whatever) or 5.5 (cos of CO2), that doesnt really mean it is acid or alkaline. The acidity is a function of the dissolved ions, which in tank water there will pretty much always be very little. So a high/low pH doesnt mean a lot of acidity/alkalinity, there is no buffering capacityand the water will immediately go to the pH driven by the mash.


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## jimmyjack (4/2/07)

> Jimmy Jack do you have a couple flushes (sorry the technical name escapes me at present) for downfall water before it starts to top your tank. That is the first amount of rain goes down the drain whilst most of the dust and crap from your roof is being washed off by rain.



No first flush, but my roof and gutters are pretty clean. I seriously cannot see any nasties coming through a 90 minute vigourous boil. Tasted the water yesterday and it is great tasting compared to town water. I am of the opinion that the final product will speak for itself. I also think that the rain water will be better than recycled poo water, water from hospitals and chemical industrial plants going through a treatment process. I am sure that recycled water is just fine but it is horrifing to think what nasty crap gets recycled. However I still may consider getting a filter for the rain water tank so my family can drink the water as well. TA for all the replies


Cheers, JJ


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## tangent (4/2/07)

> However I still may consider getting a filter for the rain water tank so my family can drink the water as well.


 Heaps of people in SA drink rainwater from the tank, no filter needed but if you feel the need and it makes you feel good, do it.
I'd rather spend the filter money on a decent mill.


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## jimmyjack (10/2/07)

> No first flush, but my roof and gutters are pretty clean. I seriously cannot see any nasties coming through a 90 minute vigourous boil. Tasted the water yesterday and it is great tasting compared to town water. I am of the opinion that the final product will speak for itself. I also think that the rain water will be better than recycled poo water, water from hospitals and chemical industrial plants going through a treatment process. I am sure that recycled water is just fine but it is horrifing to think what nasty crap gets recycled. However I still may consider getting a filter for the rain water tank so my family can drink the water as well. TA for all the replies



Got the filter yesterday from Rossco. Thanx Ross for the great deal, the next best deal for the same filter was 128.oo at Capalaba. You saved me heaps mate!!! I have it connected to the kitchen sink and the water is so much better tasting. I still do not know if I will us it for the rainwater tank but at least I have that option now. Next Ale I do will be 1/2 tap water through the filter and 1/2 rainwater + some Gypsum. 

Cheers, JJ


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