IME my crayfish haven't dug at all. I had 3 in a 10 gallon and yes, they did all die suddenly (although I do think it was because of bad water quality) I've had my current one since November and he's still going strong, but he is a Dwarf Blue Crayfish, not a CPO (much prettier
IMO) Most CPO's are inbred in large fish farms in Asia, so due to poor breeding and shipping from all the over there is really stressful. These little guys are probably the most popular because they are for planted tanks and aren't supposed to dig or uproot plants. This is all just from my experience. They're really cool, with a hefty price tag, but still cool!
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My tanks (so far

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5.5 gallon Planted Dwarf Puffer tank (2 Dwarf Puffers and a lot of RCS!)
16 Gallon Planted
(GBR pair, 3 amano shrimp and a whole bunch of snails!)