The device is compatible with Paterson Super System 4 development tank system, so you only have to buy one small device. 

Utilising a Paterson Super System 4 tank enables you to choose a tank size that suits your needs. You can process up to 8 rolls of 35mm film in one go!

AGO turns Paterson tank to rotary processor  which saves up to 60% of chemicals depending on the tank size. While it is also possible to use in vertical configuration, but then without time compensation.