In my experience (your mileage may very), I use the Foundry as a EBIAB (Full Volume, No Sparge) system, and just use more grain to make up for efficiency losses that naturally having with no sparge. That is why many will run into poor efficiencies when trying a sparge-based process.

(Maybe a gallon, which isn’t really enough to accomplish a good sparge and rinsing of sugars from the grain). Anyhoo, if you compensate for the large deadspace (not mash tun loss, I’m talking recoverable deadspace), you won’t have much sparge water. Therefore, when you mash, you will have a very thick mash that will be difficult to mash properly and homogenize, resulting in poor conversion. Anvil Brewing Equipment: Inspired by Palmer, Built by Blichmann, and Made for You The lineup includes kettles, propane burners, false bottoms, scales, thermometers and more. Northern Brewer carries the 7 and 14 Gallon Anvil Crucible Conical Fermentor, the 6.5 and 10. These homebrew components have the same product development, quality, and satisfaction guarantee, but with a lower entry point for aspiring homebrewers. From the triple element low watt density dual voltage heaters for blazing fast heating speeds to the unique high flow grain basket, you won't find a more powerful feature-rich product. You can rest comfortably knowing that Anvil equipment is backed by two of the biggest names in the homebrew industry. Anvil Brewing Equipment is a new line-up from Blichmann Engineering. If you don’t have this deadspace factored in your profile, it will calculate less strike water needed. The ANVIL Foundry is the most versatile all-in-one brewing system available, at 10.5 gallons it is perfect for 5 - 6.5 gallon batches.

This is the amount of space inside the Anvil but outside the malt pipe that your mash is never going to touch. With the 6.5, I factor in about 1.5 gallons of deadspace. As an earlier post mentioned, you have to consider all the deadspace you have around and under the malt pipe when you calculate strike and sparge water requirements. Back to OP’s question - I have a 6.5, not a 10, but I have not had great success with any amount of Sparge process on the 6.5, when using the Malt pipe.

Anvil brewing equipment