Brew day, a new mash tun, and horrible efficiency..

So my friend and I brewed today with a new polarware mash tun, and our efficiency SUCKED! It wasnt the tun itself...it held its temp perfectly, and there was no stuck mash or anything, but the height of the false bottom creates a good 2-3 inches before the grain bed starts, which i believe held water that didn't steep with the grains. Not only that, but I didn't take into consideration that it would thicken my mash up, so we had a very very thick mash. I designed the recipe/strike water to equal out to about 1.25 qt/lbs but it looked more like 1 qt/lbs.

We ended up getting 61& efficiency, which is the worst i've had in a very long while. Any tips on how to gauge for the gap created by the false bottom? Was I right assuming that my poor efficiency was due to the gap, or was it somewhere else along the line? We hit 5 gallons at the end of the boil, like clock work, and there weren't any problems with the mashing itself, just the steeping, i do believe was to blame. Any advice is greatly appreciated.

Were you doing any recirculating or just maintaining the temp of the MLT?

Maybe try 1.5+ qt/lb. Also, either after, or during the mash, you could run off the water in the bottom (assuming it will drain first) and dump it back in the mash.

We recirculated to clear the wort before putting it in the boil kettle. The color was spot on for what we were shooting for, so we assumed that everything was normal. Yeah, I figured 1.5 might be better than 1.25 for something like this...thanks for the help.

You may have had poor conversion efficiency due to the thick-mash. Thinning it should help if that's the case. EDIT: mashing longer would likely help too.

It might help to take a few quarts (throughout the mash) through the valve and pour back on top. I'm just getting used to a Blichmann Boilermaker and have been doing that. I also have a thicker mash due to the dead space, I've been doughing-in @ 1.4 qt/lb (and then infusing to a second rest temp, it's a Hockhurz-infusion mash) but this is a different brand brewkettle.

Since I have to mash thinner and don't want to 'use up' all my sparge water; and I like doing a 2-step mash plus mash-out, I've moved to doing a liquid-only mash-out decoction (~5 qt) to get from 160 F to 168 F. You might consider that too.