Rain Water For All Grain

[Jethro]

My next door neighbour has a rain water tank and has suggested I try some for my brew While doing partials and extract I felt that as not all the H2O would be boiled that there may be a bug or two that may spoil the brew but I guess with a full mash as the full wort is boiled that should not be a problem. are there any other reasons against PH for example or should I give it a go. (itle save filtering with my 1 litre jug) cheers
Jethro

 

[GMK]

I have added rain water straight from the tank to the fermenter with no problems...

 

[pint of lager]

Rainwater can contain all sorts of unwanted input. Possums, birds and even batz fly around and land on the roof, goodness knows what ends up in the tank, even with a first flush diverter and screens.

The dead possum with associated very alive maggots drowned in the tank with toilet flush water.

I give all tankwater a good boil before adding to the fermenter.

 

[Gulf Brewery]

Hi Jethro

I use rainwater for my lagers without hassles (and tap water for my ales), though I have had a couple not ferment out as far as they should. I think the water may need a bit of calcium added into it to keep the yeasties happy.

Cheers
Pedro

 

[Rubes]

eeek! Possums with maggots. Nice. Reminds me of a time I went hill walking in Scotland. Out in the middle of nowhere. A mate and me stop to fill up water in a stream. Nothing like pure fresh water we say. Better than all that city crap. You can really taste the difference..... 20m further up the hill we come across a well bloated half sheep. Up close the stench was too much. I up-chucked there and then. Yum!

 

[PostModern]

Cheap filtering method:

Materials:
1 standard plastic bucket
1 Britta filter jug cartridge

Tools:
Hole saw or Stanley knife.

Method:
Cut a round hole a bit smaller than the thick end of the Britta cartridge in the bottom of the bucket.
Push filter cartridge into hole.

Use:
Rest sterilised bucket on top of HLT or bottling bucket or fermenter. (couple of sticks of 10x25mm timber help if your vessel is larger than the base of the bucket). Add water to bucket. Notice clean active-carbon filtered water enter your capture vessel.

The filters are good for about 200 litres, if memory serves. Should be good enough to filter out the majority of bacteria, soot etc from rain water. I'm using mine to reduce chlorine and heavy metals from tap water.

 

[pint of lager]

Great idea postmodern, thanks for the input.

Could you check the packaging and see if they make any claims to what the filters remove and how much? Especially, is it effective against bacteria and yeast?

Treated water sould be used promptly after filtering, as bugs will reinfect and micronutrients will be present meaning the bugs will grow again.

My method for sanitised water from the tank for brewing kits or top up water. Sanitise a spare fermenter and fill it up with boiled water from the kettle. Store somewhere cool and out of the sun. Chuck water out after a week.

 

[PostModern]

Could you check the packaging and see if they make any claims to what the filters remove and how much? Especially, is it effective against bacteria and yeast?

According to their website http://www.brita.com.au it removes 99.9% of guardia and crytosporidium. I'd assume it'd work on most other bugs as well. Also, it only removes positively charged ions, so things like flouride will come thru. It is effective for chlorine, alum and a few other additives.

On the negative side, the jug cartridge that I use is only recommended to filter 6 litres per day to let the ion exchange beads "properly handle the adsorption / absorption cycle and still provide optimum results". Still, you're bound to see some improvement and, with rain water, I'd mostly be concerned about soot and rotting possum flesh, which the activated carbon should still be able to deal with.

 

[Doc]

I use the Brita on tap water filter for brewing.
Got the father-in-law to install a tap in my brew shed.
I've used it for all of my brews ever (from when I started with K+K to now AG).
Only thing I've found is that getting near the end of the life of the filter the flow rate drops off. It takes a little longer to get you brew water, but at least you know it is good water.
I don't see that you couldn't connect up a tap and use the on-tap version to filter the water for you.

Beers,
Doc

 

[Rubes]

On a slightly different tack is rainwater suitable for mashing? I would imagine it would be pretty close to distilled water in profile so lacking most minerals etc. Not an issue for kits but .......

 

[chiller]

Hi Rubes,

The answer to your question is yes and no. Yes it is fine for mashing but no it is not like distilled water.

The region you collect the water in will have a large impart on the dissolved salts in the water. Near the sea [within a kilometre] the salt levels could be very high whereas 30ks inlad the water will be very different.

How clean are the gutters?

How does the water taste? Flavours or metallic tastes?

What is the pH of the water?

Now having said all that if the water taste fine and is clear not murky it will be excellent for mashing.

For mashing with my rainwater, I assume a low level of minerals and use Calcium chloride in the mash to provide the nesacarry calcium for the enzymes to do their thing to reach the optimum ph. Depending on the beer you can also use Calcium Sulphate.


Recommended minimum calcium levels for mashing are 50 ppm so if you assume rain water has very minimal calcium you can add either of the salts to achieve those levels.

I live about 20ks from the coast so my tank water is reasonably neutral [ph is 6.8 most of the time] and reasonable salt free.

To freshen the taste of a tank an activated carbon filter works very well.

Steve

 

[pint of lager]

My tankwater also is slightly acidic, 6.2 to 6.5. The local soil is around 5.5 so any dust will lower the pH.

To work out salts additions, I use promash and put my water profile as the same as distilled water, then decrease the amount of salts by 10%.

The tanks are fitted with first flush diverters.

To remove most of the soot. The roof is corrugated zincalume. We run two fires. The roofline around the chimneys is extended past the gutters, so the water from that part of the roof runs onto the ground, not into the gutters and tanks.

 

[Guest Lurker]

I wouldnt worry too much about the pH of your rainwater tank. It will probably be a bit below 7, mainly I think due to CO2 dissolved from the atmosphere. But I wouldnt really call it acid because in most places it should have very low ionic strength, ie zilch buffering capacity. So I would expect the pH of the mash etc will be completely controlled by any salts you add and the grain.

 

[chiller]

With a light coloured beer the pH [on the lower side with rain water] is not as critical but when you start making a stout or any beer with dark grains you can very easily drive the mash too low because the low salt content of rainwater does have only a minimal buffering effect.

As an example my rainwater requires less than 1ml of 85% phosphoric acid to lower the ph from about 6.8 to 5.8 whereas with Adelaide water the required amount is much higher and when the buffer is broken the ph drops very quickly.

Dark grains will by their nature drop the pH of you mash especially in rainwater if salt content is low. As much as practical I do advocate some method of checking water and mash pH if you wish to keep within the accepted brewing guidlines.

Water ph is important, you can make a perfectly acceptable beer without knowing the pH but if a fault continues in a beer that you cannot identify there is a possibility it is water/pH related.

Again light coloured beers benifit from a lower mash water ph whereas darker beer can cause too low a mash pH.

Steve

 

[bonk]

ok, weird question time,

if you had a counter pressure bottle filler and one of the above filters, could you filter the yeast and anything else out and fill your bottles.

ie trick your megabrew mates into drinking no sediment crystal clear homebrew ?

 

[Jethro]

Wow a lot of advice there well I'going to try the brita filter in the bucket trick and also try to get some kind of grip on the salt addition and P.H. thing. By the way are there any laymans terms for calsium chloride and calsium sulphate. And how much would you add? Do you add the salts to the mash water only or to all water used. I am planning my next Beer to be a Bavarian/Dunkel so I guess that is in the dark beer catagorie. I thinks theres a lot to learn in this all grain Brewing!
I live 40 kms inland off Perths coastland and the neighbours rainwater tastes better than the tap thanks to recent rains. Cheers for now
:blink: Jethro
By the way is there an easy way to test P.H.

 

[chiller]

Calcium Sulphate is Gypsum and Magnesium Sulphate is Epsom Salts, as for Calcium Chloride .... Not sure if it has a user friendlier name.

Get on line and google water chemistry for brewing.

Find out a water profile for the beer you want to brew ... do your calculations based on your water then post them and someone will offer help.

It is far better to learn from your own research and then put that up for discussion.

Doc has posted a link to a very useful water chemistry utility that can be downloaded for free.

Steve.

 

[Jethro]

Thanks Chiller Ill do that, Ill just get my next brew on with tap water and hopefully
I will find time to get it right for the next brew. (hard to find time with a 4 year old daughter wanting constant attention and the missus wanting stuff done around the house) I guess that for rainwater it should be presumed PH neutral and no minerals. As for Bonks question about using water filters for beer I would imagine that the carbon filter would strip colour and flavour out of the beer and also would cause a high level of oxygen pickup and so I would not try it myself. any other views? cheers
Jethro

 

[chiller]

Perfect what you are doing and as you are comfortable more to whatever you feel is the next brewing step.

Presumption of neutral is reasonable.

Good luck with the domestic juggling act

Steve

 

[GMK]

Chiller is right with what he says.

Common name for calcium chloride is Chalk.