Cleaning Jobo Processor between different chemistry

Hello all,

I've got quite a backlog of film to develop and I'm hoping my Jobo (CPA2 with lift) will help expedite the process. I've got a couple multi tanks and an expert drum for some 4x5 sheets. Ideally, I'd like to run successive rounds of C41 since the chemistry will be at temperature. But I'd also like to be able to run a tank of BW rolls before hand when the temperature of the bath is cooler. I know that dry reels are crucial so the plan is to have enough reels so as not to reuse any and just dry out the tank/spindle/lid enough with towels so that the dry reels and undeveloped film don't have any issues.

My question is regarding the process to ensure the Jobo is clean enough to not cross contaminate when switching from HC110 to C41 or E6 chemistry. Heck, I'm sure if I did successive rounds of the same process I wouldn't want the last chemistry tainting the first (ex: trace elements of fixer mixing in with fresh developer). What I've been doing is washing the film while the drum is still attached to the Jobo instead of pulling it off and washing the film under running water. I figure that doing so would help dilute and rinse any chemistry in the Jobo housing. Hopefully, successive rounds of fresh water and rotation would eliminate all (or close to all) of the chemistry residue. What I've done to date is just 8 or 10 fills of fresh water with 30 seconds of rotating each time. Is that enough to ensure that any trace amounts of chemistry are rendered insignificant when the fresh chemistry is put in minutes later? Should I put my hose up to my Jobo and have running water pour through the top while the lift is down and again while it is up (to clean out the spent chemical hose)?

Thank you all in advance for taking the time to help me out with this.

-Omid

hi omid

i clean my jobo atl2+ with hot water mixed with citric acid(critals). for this the jobo has a cleaning program. in the cpp I guess you have to do it by hand but this should be enough
one full bottle each with hotwater+citricacid and then 2 times more just hot water. It is what i do and has never failed me

this is what jobo recomends for cleaning the processor and bottles.

it works great as I often do b+w white before I run C41

hope this helps

The acid makes sense as intermittant cleaning program. But inbetween processing runs such makes no sense to me

Thanks to both of you for your responses. With regards to citric acid would something as simple as diluted Ilford Ilfostop work or is there some other brand you’d suggest?

The acid people are talking about is to do a clean of built-up residue. All you need to do is to pour about 500ml of water through the lift to rinse out the last chemical used.