no hard tanks yet in 2000, and an enzo sack wont work in the older boats because of a fiberglass bulkhead between the vdrive locker and under the side bench but. A 750 in the locker and 750 on the bench (we use 400lb sac and a couple people.) 1500=enzo sac. Add a little in the nose for a longer pocket and you are golden.
You don't need that much, we started with two boxes full of rocks, then to one 500# sac then two, then a 750 ect.... Surfing was fun no matter the wave size, but you are always wanting a bigger wave.