Not to be Dougie Downer, but if I remember correctly you had quite a few issues with some clowns dying off a bit ago because of lack of knowledge about SW
systems. It's a learning curve you went thru and hopefully gained some experience from the ordeal.
If you want to consider a Mantis, you need to do a lot of research before just jumping in. There are different (spearing and smashing) species but most require a 3' tank, a good sand bed, and good water flow. They are predators and can attack fish much larger than themselves. No fish is safe, nor any type of cleanup crew. You're much better off with a thick acrylic tank over glass as it's quite possible for them to break it. Have you seen what they can do to a clam shell ? They can be very hardy but require very pristine water conditions.
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