Do you foresee any long term problem with hard use, water, blood, ect. with the glue? Does it break down?
Pretty much ALL glues will eventually fail, it's inevitable. Cyanoacrylate glue forms a clear acrylic plastic when it cures. It's similar to plexiglas. I've been using loveless bolts on the knives with glued handles to give some mechanical attachment in addition to the adhesive.
Aquariums are made from acrylic, so water and water based liquids like blood should have no effect on the glue directly. Long term exposure to water can damage natural handle materials however, and rusting is an issue with water as well.
Acetone will dissolve cured CA glue (and a lot of other adhesives). So I'd suggest keeping the knives away from products containing acetone.