I was thinking:
I do 1 one hour dive a week. Between dives I seal the scrubber cartridges in an plastic bag or tupperware box.
Before dive 3 I put the bottom cartridge in the top, refill the former top-cartridge (it's has done 2 hours) and put it in the bottom.
At dive 4 the scrubber cartridge (now in top) is almost 4 weeks old (after first packing)
Is this safe?
Or in other words: How long is it safe to use scrubber after first use?
I don't want to take unnecessary risks, bus I don't want to waste scrubber as well..