yes 2-1/2 x 10 is just right. i installed a 4-1/2 x 10 on mine when i built it and the cost of those filters is just too high. the saving grace is i can run the 2-1/2 inch in the 4-1/2 inch housing with a home made collar that i slip over the outside of the 2-1/2 inch filter to center it in the housing.
Tim Schmidt
2013 13 Taps 4 Gallons Syrup, Drum evap.
2014 50 Taps 14 Gallons Syrup, Drum evap.
2015 60 Taps on 3/16 gravity, 40 Taps on buckets, 42 Gallons Syrup, Home built 30 x 60 arch and flat pan
2016 125 Taps all on 3/16 gravity average 18 in. vacuum, 43 Gallons Syrup, Same Arch and Pan
2017 125 Taps all on 3/16 gravity average 18 in. vacuum, 44 Gallons Syrup, Same Arch and Pan
2018 155 Taps all on 3/16 gravity average 18 in. vacuum, Same Arch and Pan, home built 100 gph ro unit