I've seen my crayfish nibbling on my sword plant. I've also even seen him dig up a root and take a nibble! And yes, they definately like to dig around the roots! I find that if I give him lots of hiding places he'll stay away from the plant though. I think he mainly digs at the roots in attempts to make a hiding place! lol Good luck!I have a 20g planted tank that has nothing but TONS of plants... The plants are a must... will a blue lobster eat plants?