the 10 gallon round coolers are very expensive... I only used one because I figured the round coolers gave me more leeway with grainbed depth from 5 to 10 gallons. Having a smaller footprint would help ensure I had a good grainbed pretty much no matter what I decided to brew....
That being said...... you coupld probably build 2 or 3 square/rectangle coolers with either CPVC manifolds for fly sparging or stainless mesh for batch sparging for the price of a round cooler and a good false bottom........
for normal 5 gallon batches the igloo icecube I think its the 30 or 32 quart is perfectly square and would be EASY to make a manifold for..... the larger icecubes I believe all have a wheelwell in the bottom that I would think would mess with operation.... but there are a ton of other flat bottom rectangular coolers you could use for bigger batches.....
I used the 48qt icecube for my HLT.... I like the way the valve is angled I just bent a peice of copper pipe to form a pickup tube on the inside..
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