Mash Tun size and grain surface area

Looking to build a mash tun from a cooler. New to AG and will be brewing 5 gallon batches, but want to prepare for larger batches in the future.

The question is, if I get a 150 QT cooler, that is a large rectangle, will there be issues with five gallon batches where the grain bed will be shallower?

Thanks!

 

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I’d be concerned with how much liquid will be left in the cooler after you finish draining. Do you have a spot picked out for the spigot? You’ll have to adjust your recipes to account for that amount of ‘loss’. The larger base on the cooler the more loss you could run into based on how low you can get a spigot installed.

 

Interesting, I didn't think about that, the one I had my eye on has a spigot on the narrow side. I was also concerned about how difficult it would be to adjust temperatures during mash in with that much surface area. Not true if that is true or not.

Maybe I'm overthinking it and should just go with a smaller cooler for now and trade up at a later time.

 

I think 150 qt is WAY too big for 5 gal batches. I'm doing 10 gal batches and thought that 125 qt was too big. Your mash will literally only be about 2 in deep. I just got this one from Amazon. http://www.amazon.com/Coleman-70-Quart-Xtreme-Cooler-Blue/dp/B000G64I1A/ref=sr_1_4?ie=UTF8&qid=1316202177&sr=8-4