You should be able to process 5 rolls according to Jobo 1500 drum specs - 900ml chemicals for 5 220 rolls. I do 3 220 rolls with 660ml in 2502 drum using ATL-1000 and CPP-2. Here is Jobo AG link.
Regards
Ed
http://www.jobo.com/web/1500-Series-Tanks.336.0.html