Cooler Size for 2.5G All-Grain Batches

Hey, I have two questions. First, I want to brew half-batches of all grain and am wondering what size cooler to convert to a MLT. I've seen the great threads on here that suggest a 2G to 3G cooler, but just thought I'd ask what folks around here would recommend. I'll be using 4-7 lbs of grain most of the time, so I'd like the cooler to be ideally suited to that batch size.

Second, I'm wondering how big or small I could I could go with that ideally suited cooler (i.e. what are the practical limits to the amount of grain that I could put in a 2G to 3G cooler?).

I brew half batches in a 5 gallon cooler. Usually there is a lot of head space but I don't think I'd go smaller. If you had to you might be able to do 3 gallon. But if your going to buy a new one just go for the 5 gallon for some extra room to play with.

You could just mash in your brew kettle with a grain bag in a warm oven.
To estimate mash volume, check out this calculator:
Can I Mash It?

5 gallon cooler = 2.5 gal. batches
10 gallon cooler = 5 gal. batches

and so on.

This way you have room for larger grain bills, water infusions etc.

Thanks. It seems like I'll be around 1.5 to 3.5 gallons with my grain bills, BUT I noticed a link discussing cooler size and grain bed depth that suggested the grain bed depth doesn't really matter for batch sparging. As far as limits go....So as long as I batch sparge, it seems like a 5G would do just fine. If I fly sparge, I'd probably want to pick up a 3G. To be honest, I have no idea what the difference is, but batch sparging sounds like less of a hassle.

robertjohnson said:

Thanks. It seems like I'll be around 1.5 to 3.5 gallons with my grain bills, BUT I noticed a link discussing cooler size and grain bed depth that suggested the grain bed depth doesn't really matter for batch sparging. As far as limits go....So as long as I batch sparge, it seems like a 5G would do just fine. If I fly sparge, I'd probably want to pick up a 3G. To be honest, I have no idea what the difference is, but batch sparging sounds like less of a hassle.

Click to expand...

IMHO fly sparging CAN be easier... because if you are good at it, you open two valves and walk away. Come back 40 minutes later and it is all done, the HLT is dry, the MLT is dry and the kettle is full. No dumping in water, stirring, varlouf, drain, pour, mix, varlouf, drain... ugh!!

I am mowing my grass during the sparge, batch spargers are pouring, mixing, varloufing, draining, pouring... etc.

I've done 2.5g all grain batches in my 2 gallon cooler, but I don't recommend it. 5 lbs of grain is about the most I can do with any efficiency so you'll be stuck with lower gravity brews.

I can do 3 gallon batches below 1.06 in my 3 gallon MLT cooler. If I had the space I would have gone with at least a 5 gallon cooler, but alas, I live in a condo and we didn't have room for it on the counter, and SWMBO didn't want to store it.

If I do a 5 gallon batch, or a 3 gallon hi-grav, I just do a partial mash. Works great for me, 3 gallons is a good amount for me to drink in terms of volume and price per batch.

I do almost all grain batches with 7lbs of grain and 1-3 lbs of extract and/or sugar in a 5 gallon cooler. Works great, and I hit 80-82% efficiency IF my mashout hits 170F (last batch missed this by about 5 degrees and came in at 72% efficiency because of it).

I put a 5 gal paint strainer in my 5 gal cooler, and add the grains
I add 13 qts of 168F water to this (hits 154F or so), do hour rest/converstion
I add 6 qts boiling water to the cooler to mash out at 170F, stir and leave it 10 min
I pull the bag out of the cooler, and dump the wort into the brew pot.
I put the bag back in the cooler and add 4 qts water at 170F, stir and leave it 10 min
I pull the bag out again, and add the sparge to the kettle and start the boil
During the last 15 min i add whatever extract/sugar I need to get my gravity where I want it.
I usually collect a little less than 4 gallons for the fermentor this way, so I add a gal of water (this helps to cool it down too)

This works for me, tastes fine (so far) and means I can do everything in my kitchen. I can do true all grain if I just want 4 gal batches, or if I want 5 gal session beers (less than 1.040 SG). Its sort of a Brew In A Bag method, just with 1 final sparge and less water.

I always do three gallon batches because I like brewing more often. I use a 5 gallon MLT and I wouldn't even consider getting one smaller, though I do mash on the thin side. It also depends on the gravity of the beers you make... When I did my monster porter (>1.100 O.G.), my mash tun was absolutely and completely full.

I wouldn't go smaller than 5 gallons unless you both know that you will never choose to mash thin and that you will never do a big beer.