It depends what kind of mantis you've got. Some get big, some stay small, some spear fish, and some smash inverts. The trigger would probably eat the mantis, though.
Here's a good site:
http://www.ucmp.berkeley.edu/arthrop...raca/royslist/
I have a G. smithii in a 6 gallon display tank with a three-stripe damsel. They're getting upgraded to a 13 gallon display tank pretty soon.
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Sc replays