The CPP2 hits it's limits with 8 rolls of 35mm. That's not the reccommended that's the most rolls you can use. This assumes you're using the 1500 type tanks. With the 2500 type tanks the limit is even lower. The problem is the motor can only handle 1litre of chemical. At least according to the factory.
The amount of chemical is the greater of what the tank requires and what the process requires. It could be 250ml it could be less it could be more.