Ideas for a twenty long planted aquarium

That depends, are they temperate, subtropical or tropical, and what is the pH of the water?
 
We only had a crayfish for a VERY short time with fish. Not a good combo, the cray built a hiding spot & tried to "pinch" any fish (platy sized) that wandered too close.
 
They really are best on their own...but you still need to say what species you have. Dwarf crays can be kept with fast moving mid-top water fish without problems. The 'big' crays aren't trusted with fish...nor most plants, honestly.
 
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