well it would be a close match.. the gramma has a wide jaw, and big mouth, meaning more teeth, so i wouldn't be to surprised if the gramma tried to bite the strawberry in the face.. and bite it's entire face.., but strawberrys are really mean, wicked fast, and have more of a ripping mouth style, it could go either way, but i doubt the gramma could catch the strawberry., you can't really tell who will win, and if ANY of your fish go with the mantis they will SURELY die.., ever consider putting the gramma in the reef?