i am interesrted in moving to all grain brewing. what is the best igloo cooler system to you use?
Most of the Igloo cooler systems are overpriced, IMHO. Check out Denny’s site for advice on building a cheap and easy mashtun
http://hbd.org/cascade/dennybrew/
A rectangular cooler is a lot easier to use than a round one, in my experience.
A 70 qt. Coleman Extreme is the choice of a lot of people.
+1! I got my rectangle Rubbermaid cooler on Craigslist for $10 and built the mash tun. Lots of videos online on how to build it. If I were to do it again, I would probably go the easier/ less $$ route like Denny’s instead of going with a ball valve.
+1 to the rectangular 70 qt Extreme ( and if you want good conversion you’ll get the blue one !). I used the round Igloo for years when I fly sparged, and I love the Extreme for batch sparging so much better. Dennybrew all the way !
+1 It’s what I use.
I agree too!
I use one and love it.
here is what I did: http://brewing.lustreking.com/gear/mashtun.html
I use an Igloo Cube with a copper manifold system. The drain unscrews and my ball valve fit right in. I think it’s 60 qt. I have made 10 gallons of 1.070 or so beer in it a few times. It was full but did the trick. 70 qt would probably be ideal for size. I like my cube because I had bought it several years ago but rarely used it because it doesn’t fit in the trunk of the car. So it wasn’t any extra cost. I don’t lose and temperature over an hour either. Just make sure you buy a blue cooler.
I have a modified 10 gallon cooler for large batches and an unmodified two gallon cooler for smaller batches.
How many pounds of grain could this cooler hold?
I use a forty quart white rectangular (marine) igloo cooler and do 5 gallon batches with it. It holds easily 25 pounds of grain with strike water, but if you want a thinner mash or do bigger beers a lot, the 70 can handle pretty much whatever you need and with batch sparging, you simply sparge a second or third time, if necessary, for a monster grain bill. If you are doing a lot of big 10 gallon batches, then consider a bigger one yet, I suppose, but then I go to my 3 keg system for that kinda batch.
I have had >30 lbs in mine. it was full to the brim but I mash fairly thin.
I just spent some quality time looking at cooler options. Seems a lot of the Cube styles have a beveled edge where the drain goes, I think that would mess up draining things. I ended up buying a 48qt Igloo Marine rectangular cooler, it has a normal drain position and an indented area inside so the braid will sit low.
I alreay have a 5gal round cooler, a 60qt Extreme and a 100qt Extreme. I mostly use the 5gal cooler but will be using the 48qt for 5gal batches.
Also recently scored a new 10gal pot, so I have 3gal,couple of 5gal, 8gal 10gal, and 20gal. I’m about covered now.
What purpose does so many coolers serve?
The equation I use is total volume = (lb grain)0.0933 + (lb grain)(qts/lb ratio)/4
Check this out…scroll down the page a bit…
C’mon, now - you all know it doesn’t matter what cooler you get as long as it’s BLUE. 
+1.060!
+1 70 qt. Coleman Extreme with a CPVC manifold.
I love this thing man.
Manifold? How last century!