I'm putting together my all grain setup and I'm all ready to do my first batch tomorrow. I used a Coleman Xtreme cooler that I already had left over from a camping trip its a great cooler in good shape. I'm worried however that since its SO big, the grain bed won't be deep enough. I'm using nine lbs of grain on my first batch,which is the smallest batch I'd ever do, and when I put it in the cooler without the manifold the grain bed was just under 2 inches deep. From researching around here I understand that to have a good filter through the bed you need 4". How important is this and should I just buy a smaller cooler? I'm doing 5 gallon batches now and I'm thinking when I do go to 10 this will be ok, so I don't want to buy a small cooler that I won't use in four months