Hey folks, so we've just bought the Fluval Flex 15 gallon tank, all very nice however my son and I are considering introducing freshwater shrimp to the tank. My concern, however, is the grill slats that allows water to the rear filter system are too large and I'm concerned the little critters will get through. Would like your advice on a solution to further filter these slats without adding undue stress to the pump. Thanks all.