# Biab Water Amounts



## swellbow (23/4/10)

Hello knowledgeable folks. I've got a practical question for BIABers. I know that I want to mash with all the water I would use for mashing, sparging, etc. But do I always use a specific amount of water per kg of grain, or do I fillerup no matter how much grain I have in my recipe? And if I don't fillerup, then I guess I may have to use some water to top up to boil volume if I am making something lower gravity. If the ratio is set, then how much water per kg?

I've been reading for weeks and can't seem to find a definitive answer. Thanks!


----------



## sid (23/4/10)

I think this would depend on your type of kettle and also the burner you are using for heating.......... when I first started with my 50 litre kettle and 3 ring gas burner, I used 32 litres water (mash) and came out with 20 litres after the 90 mintue boil off..................now I use around 40 litres to start and around 5.5kg-6kg grain to end up with 25 litres of beer at around 5.5%-6% alchohol.

all depends on your set up, so you'll have to experimant a bit.........................if you fall short on your gravity, throw a bit of dextrose in when you put it in the fermenter, I never go more than 10% of the grain bill though.


----------



## Cocko (23/4/10)

Math goes like this:

You are gonna lose about 1L per Kg of grain - then 10-15% to evaporation!

You want say: 24L of wort post boil - you will lose a bit to trub and kettle loss, as in... you will not be able to drain the kettle dry, unless you have the worlds best pick up tube!  

If you use 5kg of grain. You will lose 5L here.

And then [up to] 15% more during the boil... Boil evaporation is dependant on kettle shape, size and boil rate etc....

SO: I will use 15% boil off rate for the example...

From here we work upwards;

15% of 24 = 3.6L

24+3.6L= 27.6L

then 1L per kilo of grain loss = 5

27.6L + 5L = 32.6L

This is what you would start with, as in mash in volume.


That said, this is all approximate and is purely a guide but the only way you will find out how 'YOUR' system works, as in boil off rates, bag draining [grain absorption] etc is run it up and take measurements and adjust accordingly from there...

But that should get you up and running!

2c.


----------



## chappo1970 (23/4/10)

Cocko said:


> Math goes like this:
> 
> You are gonna lose about 1L per Kg of grain - then 10-15% to evaporation!
> 
> ...



+1 Cocko I really didn't think it was rocket science? :icon_chickcheers: 

Not that I am a pillow biter but it's full volume brewing so as Cocko has put work your way back taking into account the variables.


----------



## Cocko (23/4/10)

Chappo said:


> I am a pillow biter




+1  


:lol:


----------



## chappo1970 (23/4/10)

Cocko said:


> +1
> 
> 
> :lol:



<_< Wise guy!


----------



## Bribie G (23/4/10)

Another refinement is, once you have a few brews under your belt, you very soon just KNOW on your equipment what the level should look like in the boiler before you start the boil. 3v brewers can just keep sparging till they get there but BIAB, being basically a full volume brew, has a wee sting in the tail, in that if you are going to fill a 23L No chill cube, you need get a set level in the kettle after draining the bag, but the resulting pre boil volume is going to be slightly different if you have a six kilo grain bill or a four kilo grain bill because the spent grain takes away differing volumes of the original strike liquor. If your vessel is 40L or below there can be a bit of a crunch.

edit: and of course it all depends on whether you are doing a sixty or ninety minute boil as well. 

So what I do is that if I have a big bill, say hypothetically 5k base malt, another k of spec malts and 500g of Polenta, then after hoisting and draining I just know that, in my 40L urn, I'm not going to make the target preboil volume to get me a cube. Or as Pistol Patch and I agreed, if _only_ they made 50L urns :unsure: . However I find that a good workaround here is to do the sparge in a bucket which improves efficiency a tad, and add the extra runnings back into the kettle to get your level. We are not talking much here, I find only 3 or 4 litres at the most. As I mentioned in another thread I'm going to build a RIMS/Vorlauf/ BIAB hybrid in June, Inshallah, that will allow a degree of sparging towards the end of the drain as well, so that will fix that problem.

However that's for when you have got a handle on what you are doing, and it will soon become instinctive. Great Calcs from Cocko. 

:beerbang:


----------



## Scruffy (24/4/10)

+1 for Cocko's ready reckoner/calc -

..and we're off and rambling!! ...don't forget the extra litre or so of sloppy hops and trub/break material or so left in the bottom of the boil pot - and the odd 200ml for the hydro sample - and the litre of sludge left in the fermenter... jees, there's going to be none left!!

Me? i throw two cubes worth of water into my 60l pot (about 40l), bring up to strike (usually 69/71C), peg some voile in and drop (typically... remember... for me...) 8KG Maris or Halcyon and maybe a wee bit of crystal, i might treat the water to some chalk and or gypsum, mash for 90, pull the bag (save the crud for another BIAB mini mash or trickle a couple if litres of boiling water through it - or just dump it), then boil the crap out of the liquid for 90 and add somewhere between 150 - 200g hops - at this rate you start to notice the wort loss due to hop absorption certainly if, like me, you don't wring out the hops/hop sack (- I no longer use the sock for hops)- it's probably up to 400ml for every 30 grams of the dry flowers - less for pellets of course. But I don't wring out tea bags so I certainly wouldn't mangle the wet hops...

And while we're at it, factor in your yeast - not that it sits there evaporating, but if you get a particularly 'dynamic' strain, you'll maybe lose another couple of litres - out the bubble tube and all over your fridge/carpet/kitchen/laundry etc etc...!


----------



## Bribie G (24/4/10)

Aye Laddie, these HERMS droids don't know what they are missing. Avast me hearties :icon_drunk: :icon_drunk: 


:lol:


----------



## RdeVjun (24/4/10)

It has been touched on by previous posters, but deciding how much water to use for BIAB depends on whether sparging or not. For new BIABers, keeping the numbers pretty simple, I just recommend a full- volume mash with 6 L/kg, later on graduating to dunk sparging, so mash with 4 L/kg and sparge with 2L/kg. Fine tune with subsequent batches until familiar with the equipment.
IMO, sparging is not entirely necessary though as full- volume/ no sparge BIAB is still quite efficient without it, but I do it for decent efficiency and maximising the wort volume of over- gravity boils (to reduce SG and so utilise the hops more efficiently) where mashing 4-5 kg of grain in a 19 L stockpot and still yielding 21- 23 L in the fermenter post- dilution.

Edit: Clarity.


BribieG said:


> Aye Laddie, these HERMS droids don't know what they are missing. Avast me hearties


 :icon_offtopic: Getting all piratey hey? Might need a different keyboard:






:lol:


----------



## felten (24/4/10)

I used the set up volumes spreadsheet posted here by thirstyboy. It was pretty much spot on with my straight sided pot.


----------



## swellbow (26/4/10)

You guys rock. +1 Cocko, Pillow Biter, and Pirate Keyboard all in one thread.  Now that's what I like to see.

So regardless of how much malt you use (recipes can vary by a few k at least), other than varying for absorption to hit the target pre-boil volume, you don't worry about the "thickness" of the mash -- because you would have a different L:G ratio, eh? Or I am crazy?

I am going to roll with it, get a few under my belt, and then start looking at dunk sparging, just to understand it. I may try the no chill too, but not yet. This is great.

Super inspirational. Na Zdrowie!


----------



## Bribie G (26/4/10)

Proszę

B)


----------



## flattop (16/5/10)

RE dunk sparging, i sort of gave it away after a few fairly minor burn incidents (which could have been way worse), i found the gains weren't worth the danger and potential problems.


----------



## Thefatdoghead (7/4/16)

Quick question for BIAB ers. 

Recently did a 100L batch on my new system. Running 50L brau and 114L ss kettle together.

Came close to my gravity (slightly low) although the grain absorption was way less than I considered.

Generly im pretty close with the 1 litre per kg grain in the brau but the ss kettle working as biab was 17kg of grain in 75L strike and only had 5L lose to absorbtion. 

I used only pearl pale al malt in the ss kettle and voil with 3 roller mill gap of 1.2mm. Put through mill twice gave what i would say was a fairly reasonable crush.

Question is should I go with 1 litre per kg in my next batch or factor in what i got from the last 1st batch? 

On the first batch I ended up with 120L of 1.062 wort. Was only going for 100L so I made a dark mild in the brau while boiling the ss kettle. Was a fun brew day.

Cheers


----------



## manticle (8/4/16)

If using the same type of grain and same crush, go with the real numbers.
1L per kg is an approximated average (really ~1.1/kg) and a lot of brewing is about tweaking and understanding your system to get the results you want.

Not every fanforced oven gives the same results at 200 deg for 1 hour.


----------

