I recently added one and yes, they will move sand. Mine immediately went to digging homes under every rock i had. Now, I placed all my rock directly on the glass and not the sand so nothing has or will move even if he digs it all out.
From what i have seen him do it is definately possible for rocks to move or fall if they are placed on the sand so be aware of that. He cleared almoat all substrate from under a few rocks so they are very efficient sand movers.
The good part is that when he started he made clouds of sediment when he did all this work which actually clouded up the tank a bit. However, now that no linger happens. I should have stirred it up when i added it but he did that for me over about a week.
He has spread it up some rocks and bulldozed it up the sidea of others. For me its ok and he has not been harmfull to the corals I have which is. Ot that many and very few are directly on the sand bed. This may be an issue if i add some that are sand bed only or prefer the sandbed.
Bottom line, they moved and sift sand. This is what they do and you cant blame or get mad at them. For me, I accept it and consider it my duty and responsibiloty based on my decision to add one to clean up after it.
Mine has been well worth it as he has a great personality and is fun tonwatch as he is very active. Ok, he or she, i dont know. Also, not giving human attributes to a fish, just describing him the best way i can. ;Writing
