CPO and dwarf cajuns are the only ones i am aware of that are planted tank safe. All will try to nip anyting that swims infront but these two types of cajuns possess very tiny claws and wont harm anything other than sick or dying fish.
The other thing to be aware of is that they are territorial. Having a dozen in a 20 gallon tank may be fine. Having a dozen in a pico tank is going to be a no no.
A self cloning cray may eventually leave you with many that will need to be rehomed. CPO / dwarf cajuns require a male/female pair to propagate.
I have two orange crays (Clarkiis) in a tank with 5 tiger barbs. ANY plants I toss in get mowed down overnight. They will also eat any food that goes in for the barbs. As yet, they have not caught the barbs even though they chase them all over the place. Something really interesting though. A few months back I threw in some java moss which was loaded with RCS. A few of the bigger ones now hang out with the crays and even live in their "caves".
If you get the cloning crays, you could have fresh steamed crayfish every few months.... I'm a fisherman as much as a fish keeper and crayfish is oh so sweet. I'll never forget bringing one home from a fly-fishing trip, it was delish!
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Marmokrebs, or self cloning crays are tank wreckers.
They will mow all the plants down to nothing, and will attack the smaller fish. And they are almost impossible to get rid of.
I drained my tank down and scooped out all the substrate and went over it piece by piece so as not to overlook even the youngest baby.