I'm attempting to turn my 6.6 gallon Petco Bookshelf Aquarium into a crustacean community tank. So far, I have 2 nerite snails, 2 ghost shrimp, and 1 very large tadpole shrimp (Triops mauritanicus). These have all been getting along fine with the HOB filter that came with the tank. I've had some bad luck with my smaller tadpole shrimp (Triops) getting sucked in; they're very weak swimmers. I just purchased 2 Cajun dwarf crayfish and 5 cherry shrimp on eBay. Any advice for modifying a HOB filter for the Triops and cherry shrimp? Netting? Spong attachment? Shrimp guard? Thanks so much!