Calculating water volume

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Islandboy85

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How do you go about calculating your water volume you need for sparging? I've had some shortcomings the last few brews, and had to run indoors and heat up a gallon extra. Is there a general rule or some calculation?
 
I use beersmith and it tells me how much sparge water I need. I usually add another gallon to that just so I don't have to hurry up and heat some more if I need a bit more.
 
I also forgot to add that I am slightly confused by the terminology "drain the mash tun" when people say they drain the mash tun before the sparge. Are you fully draining the wort out, or just draining until there is 1-2 inches of liquid above the gran bed? The same question for the sparge. Do you fully empty the tun or just drain until the liquid level is at the grain bed?
 
total water=(desired post boil volume/0.96)/(0.925)+(lbs grain in mash x 0.2)+loss due to equipment. Roughly
 
V
total water=(desired post boil volume/0.96)/(0.925)+(lbs grain in mash x 0.2)+loss due to equipment. Roughly

So, if I wanted to get 6.25 gal preboil and had 10# of grist it would be 8.52 gallons total. If I'm using 1.5 qt/# I'd have 3.75 gallons strike water leaving me with 4.77 gallons to sparge. Is that right?

What is the significance of the 0.96 and 0.925 and 0.2 in the formula?
 
I also forgot to add that I am slightly confused by the terminology "drain the mash tun" when people say they drain the mash tun before the sparge. Are you fully draining the wort out, or just draining until there is 1-2 inches of liquid above the gran bed? The same question for the sparge. Do you fully empty the tun or just drain until the liquid level is at the grain bed?

I completely drain the mlt before I add my sparge water. Then after adding sparge water I completely drain the mlt.
 
You have to differentiate between batch and fly sparging. With batch, you drain the tun. With fly, you don't.

I've not yet batch sparged. I've heard that it's not quite as efficient, so I didn't want to do any worse than I already did on the last few batches, so I fly sparge. I usually have very little liquid to drain off to begin with sitting on top of the grain bed. The lady at my LHBS said to use more strike water like 1.5 qt/#. She said it helps to give a little more time to establish my flow rate before so I don't run the mash too low and then get channeling.
 
V


So, if I wanted to get 6.25 gal preboil and had 10# of grist it would be 8.52 gallons total. If I'm using 1.5 qt/# I'd have 3.75 gallons strike water leaving me with 4.77 gallons to sparge. Is that right?

What is the significance of the 0.96 and 0.925 and 0.2 in the formula?

The .2 accounts for grain absorption in the mash tun. The .96 is for loss of volume due to the cooling of the wort and at the moment i forget the reason for dividing by .925, I have it written down at home. I see that your question is about sparge calculations. Beersmith has a good tool for that.


when fly sparging I heat a little more than my total pre boil target and sparge until i have collected my target volume. Never have ran out of water that way and the unused water is great for cleaning duty. I use a refractometer to check my SG as I go. Try not to sparge below 1.002 as you may start to extract tannins.
 
The .2 accounts for grain absorption in the mash tun. The .96 is for loss of volume due to the cooling of the wort and at the moment i forget the reason for dividing by .925, I have it written down at home. I see that your question is about sparge calculations. Beersmith has a good tool for that.


when fly sparging I heat a little more than my total pre boil target and sparge until i have collected my target volume. Never have ran out of water that way and the unused water is great for cleaning duty. I use a refractometer to check my SG as I go. Try not to sparge below 1.002 as you may start to extract tannins.
I may need to get beersmith... I wasn't sure. How far to collect down, so I stopped collecting at 1.010. I just got my refractometer. LOVE that thing.

Part of the problem I had on the first batch I'll attribute to getting used to new equipment though. I got a pump and new burner. I didn't realize how much heat the SQ14 throws off and spiked my mash up to 172 in a really short time since I'm used to using a tiny crappy turkey fryer. I think that hurt my conversion a lot. After that I boiled off a bit too much also since I still hadn't figured out how powerful the burner is. It got me closer to my OG, but only yielded 4.25 gallons. I'll probably have to cut down on the priming sugar that came with it now.

It makes sense now that an equal amount of sparge water should be heated to equal your boil volume
 
I think the concept seems weird to people who are converting over from batch sparging because we're used to completely draining the tun and then only having to discard damp spent grain. If you maintain a fluid bed to the very end, you actually end up with quite a bit of low gravity wort to throw away. I don't think it's detrimental to prepare a gallon or two less sparge water though because you only expose the top portion of the grain bed right at the end.
 
I think the concept seems weird to people who are converting over from batch sparging because we're used to completely draining the tun and then only having to discard damp spent grain. If you maintain a fluid bed to the very end, you actually end up with quite a bit of low gravity wort to throw away. I don't think it's detrimental to prepare a gallon or two less sparge water though because you only expose the top portion of the grain bed right at the end.

I was thinking that would work last night. Plus not having to heat up two extra gallons would save about ten minutes on the burner heating up the sparge water.
 
There are different ways to fly sparge and Bobby mentions one way. I fly sparge, drain it all, and end up with nothing but damp/spent grain plus a tiny bit of 'dead space' wort.

You don't have to use all the water required in the mash and sparge, you can come up short and just add water to the boil to get your pre-boil volume; or boil longer if you happen to go over. Depending on your water I'd probably use distilled for that so it doesn't raise your boil pH too much.

A lot of it is just taking notes and dialing your system in. I use a homemade spreadsheet to calculate the total water required but it's tailored to my system/process. I measure (and treat) total water required at the beginning of brew day and pretty much don't measure volume again until it's all in the fermenter and it's always within a quart or so. Actually I do often do a quickie/eyeball measurement preboil but that's just to see if my efficiency was nominal. If you take the time to do a few brews where you measure volumes at each step as accurately as possible (and correct for temperature) you should be able to dial it in. Kaiser's Efficiency Troubleshooting Spreadsheet (found on this page) is a nice tool to use because in order to properly fill out the spreadsheet you have to measure volumes accurately along the way, and with a refractometer it should be relatively easy to do.
 
While we're on the topic of water volumes, can anyone explain how to calculate water volumes for a two step infusion mash? I'm brewing tomorrow, and this will be the first time I've attempted a protein rest. Beer Smith has some default values, but when I input my grain bill I get errors for the saccarification step because my infusion temp is above boiling.

I'm doing a dogfish 90 minute clone, looking at about an 18.1 lb grain bill. How can I figure out how much water I'm adding at each step?
 
While we're on the topic of water volumes, can anyone explain how to calculate water volumes for a two step infusion mash? I'm brewing tomorrow, and this will be the first time I've attempted a protein rest. Beer Smith has some default values, but when I input my grain bill I get errors for the saccarification step because my infusion temp is above boiling.

I'm doing a dogfish 90 minute clone, looking at about an 18.1 lb grain bill. How can I figure out how much water I'm adding at each step?

It takes a LOT of infusion water to get up to a sacc rest temp from a protein rest temp. It's probably saying the infusion water temp is above boiling because you don't have enough water. Try to do the protein rest as thick as you possibly can and as hot as you possibly can (you can do them in the low 130s) and see if that helps. You will get some beta-amylase activity during the protein rest (more if it's hotter) so you might want to increase your sacc rest temp a tiny bit. You'll also tend to make a slightly more fermentable wort when mashing thin (which you will be after that infusion) so there's another reason to perhaps increase the sacc rest temp a little.
 
Jiggering the options, I managed to get the following for 18.13 lbs of grain:

Protein rest - 9 qts. water at 140.3 degrees
Target temp = 122 degrees for 30 minutes

Saccrification - 8.04 qts. water at 190.3 degrees for 60 minutes
Target temp = 149 degrees for 60 minutes

Mash Out - 5.98 qts. water at 210.6 degrees
Target temp = 163 degrees for 10 minutes (couldn't get this to 168 without the infusion temp going over boiling).

Does this sound like a reasonable schedule?
 
That first step looks way too thick @ .5 qt/lb. Even after the first infusion you're still below 1 qt/lb. What are you mashing in? Does it have a false bottom and if so, how much dead space?

You can help the last step by using boiling water during the second step infusion (you'll use less water in the second step).

You don't have to hit 168* F. After mashing at 149* F for 60 minutes you should have a very fermentable wort so making it too fermentable doesn't look like much of a concern.

For 18 lb of grain I'd be using more than 23 qt of water, quite a bit more. I think that is the biggest problem I see here, not nearly enough mash water. But it seems everybody uses WAY more sparge water than I do (I'm almost to the point of no-sparge anymore but still hit ~75% efficiency into the fermenter).
 
.5 per pound seemed low to me too, but that was the default value in Beer Smith. I'm mashing in a 10 gallon rubbermaid cooler with a steel braid.

It's telling me to sparge with another 3 gallons of water, so I assume that's where it expects me to make up the difference.

I'm debating the need for the mash out. I've never done one before, but the recipe called for it. I feel like that gallon would be better used in the earlier steps, but that's just gut instinct. I'm still not very clear on how one determines ideal water ratios for the various steps.

End of the day, I need about 6.5 gallons in the boiler.

edit: It just clicked. Each subsequent step in Beer Smith is additive with the one before it when you're entering the water/grain ratio. I thought that it was calculating individually, which is why I couldn't understand why it told me to add no water when I tried breaking up 1.25 qts/lb into a .75 and a .5 step. The saccrificiation step should be a total of 1.25, and suddenly everything works fine.

I'm going to forego a mash out and just sparge at 168 as usual. It shouldn't significantly impact things, and trying to push up to 168 even for a few minutes once I've got that much water and grain the mash tun is just too difficult.

As of now, I'm looking at 13.6 qts at 134* for 30 minutes, followed by 9.07 qts at 199* for 60 minutes to reach a ratio of 1.25 qts/lb, then sparging with 2.75 - 3 gallons of water. That's more in line with what I'm used to.
 
If you're just doing it because a recipe called for it...and you're mashing 18 lb of grain in a 10 gal cooler I would definitely NOT do a protein rest. Just seems like a miserable/frustrating brew day waiting to happen. I doubt you really need that protein rest.

Now that I look back and see it's a 90 minute clone there's no way I'd do a protein rest in your shoes. Just my opinion though. Good luck either way.
 
Out of curiosity, what's so miserable about it? Now that I've wrapped my mind around the information Beer Smith is telling me, it seems fairly straightforward. Just one more infusion step. I've done big grain bills in this cooler before without any issues, just never anything with a multi-step mash.

If nothing else, it's a skill I should practice.
 
Successful brew day on Saturday! Nailed the temps at both steps without a problem. Efficiency was a teensy bit lower than I anticipated, but still well within range of a good brew on my equipment.

All in all, two step mashing wasn't nearly as hard as I expected.
 
Great, glad I was wrong about it being miserable/frustrating. If things go wrong it could be but if they go right, as they did, it's just the opposite (i.e. fun/rewarding).
 
Grrrrrrrrr!!! What went wrong? I did AHS's Arrogant Bastard Ale clone. 13.5 # 2-Row, 1.5# Crystal 120. I mashed with 1.5 qt/#. I fly sparged with 5 gallons water. I wound up sparging until 1.015 and had a total of 6.75 gallons preboil gravity was 1.050. It was supposed to be 1.074 per the recipe. What did I do wrong? By the way, I have a 15 inch false bottom, so I should be getting way better results.
 
Grrrrrrrrr!!! What went wrong? I did AHS's Arrogant Bastard Ale clone. 13.5 # 2-Row, 1.5# Crystal 120. I mashed with 1.5 qt/#. I fly sparged with 5 gallons water. I wound up sparging until 1.015 and had a total of 6.75 gallons preboil gravity was 1.050. It was supposed to be 1.074 per the recipe. What did I do wrong? By the way, I have a 15 inch false bottom, so I should be getting way better results.
The gravity was supposed to be 1.074 preboil?

In any case, just based on my system you used a lot of water just to get 6.75 gal preboil. For example, I just brewed a batch that had 14 lb grain and used 38 qt total water, I had about 7.4 gal preboil.

But without details on exactly what you did it's hard to say. You said you stopped sparging at 1.015, did you leave a bunch of wort in the mash tun?
 
The gravity was supposed to be 1.074 preboil?

In any case, just based on my system you used a lot of water just to get 6.75 gal preboil. For example, I just brewed a batch that had 14 lb grain and used 38 qt total water, I had about 7.4 gal preboil.

But without details on exactly what you did it's hard to say. You said you stopped sparging at 1.015, did you leave a bunch of wort in the mash tun?

I used a total of 10 gallons water. I stopped at 1.015 because I was afraid of leaching tannins. AHS said to only collect 6.25 gallons for the same reason. 1.074 actually is the OG, sorry; but, for some reason this time I only gained 10 points on my boil. The boil and hop schedule was a 60 min boil, so I kind of had to stick with that to keep the hop schedule. I only had about a gallon and a half in my tun when I was done. An online calculator said I got 61 percent efficiency...that SUCKS.
 
I used a total of 10 gallons water. I stopped at 1.015 because I was afraid of leaching tannins. AHS said to only collect 6.25 gallons for the same reason. 1.074 actually is the OG, sorry; but, for some reason this time I only gained 10 points on my boil. The boil and hop schedule was a 60 min boil, so I kind of had to stick with that to keep the hop schedule. I only had about a gallon and a half in my tun when I was done. An online calculator said I got 61 percent efficiency...that SUCKS.
You said you mashed at 1.5 qt/lb so @ 15 lb grain that's 22.5 qt...then you said you sparged with 5 gal (20 qt) so that adds up to 42.5 qt total water.

In any case, you can always boil longer if needed, you just need to calculate how much longer you need to boil and then add your bittering hops at 60 minutes remaining. Getting your volume and efficiency right will take some tweeking and you can accelerate the learning curve by taking careful measurements (and correct for temperature, water expands as it heats) throughout a brew day. Learning exactly how fast you boil-off and exactly how much 'unretrievable' wort you leave in the mash tun are two things I'd try to nail down first.
 
You said you mashed at 1.5 qt/lb so @ 15 lb grain that's 22.5 qt...then you said you sparged with 5 gal (20 qt) so that adds up to 42.5 qt total water.

In any case, you can always boil longer if needed, you just need to calculate how much longer you need to boil and then add your bittering hops at 60 minutes remaining. Getting your volume and efficiency right will take some tweeking and you can accelerate the learning curve by taking careful measurements (and correct for temperature, water expands as it heats) throughout a brew day. Learning exactly how fast you boil-off and exactly how much 'unretrievable' wort you leave in the mash tun are two things I'd try to nail down first.

I left that much in the mash tun because I was fly sparging. From what I read earlier in this thread you only fully drain the mash tun if batch sparging. I do't know why the boil changed. The last few batches I've done I haven't had a problem boiling off a whole lot. As a matter of fact, the last batch boiled off too much (learning to use the new burner).
Lets say for an example that I needed to get 24 points out of the boil like in my situation to reach my OG. Is there a formula that says how much of your volume you need to boil off to hit that?
 
Just multiply the gravity (in 'points') by the ratio of volumes. So if you start with 6.75 gal of 1.050 wort (i.e. 50 points) and you're boiling down to 5 gal: 50*6.75/5=67.5, so your gravity when you boil down to 5 gal should be 1.0675.

You can fully drain the mash tun when fly sparging. You do have to be careful of over-sparging but you can prevent that by not using so much sparge water and having good mash pH. You shouldn't lose much efficiency IF you were going to extract tannins by sparging further. As an example, I brewed a Mild a while back and only sparged with 4 qt (and I added that pretty early in the sparge so this was almost a no-sparge brew) and I still got 74% efficiency into the fermenter.

EDIT: To calculate 'how much should I boil off to gain 24 points' just multiply your current volume by the ratio of gravities to get your final volume, then subtract the final volume from the starting volume: so you have 6.75 gal of 1.050 wort and want to hit 1.074; 6.75*50/74=4.56 gal. 6.75-4.56=2.19 gal.

If you're ever not quite sure if your ratio is correct (i.e. is it upside down?) just intuitively think of what is happening. If the volume is decreasing the gravity is increasing so you need to multiply the gravity by a number >1 (or conversely multiply the volume by a number <1).
 
Yeah I have always used Beersmith and added about a gallon extra to the sparge to be safe. So far so good
This last brew I had enough water, just not good extract efficiency and a crappy boil. I guess I'll just have to wait to see what it tastes like. It should be done soon since I used a yeast cake from a batch that just went into the secondary fermenter. I had to put a blowoff tube into the bucket lid two hours after I put in in the bucket.
 
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