The Trap-Pest is a universal trap for crabs, snails and bristle worms in fresh or salt water. The Trap-Pest is an automatic trap for removing undesirable bristle worms, crabs or snails from an aquarium. Bristle worms crawl through a funnel into the trap and cannot find their way out whilst crabs and snails pass through a one way curtain which blocks their return path. The Trap-pest is simply baited from the outside.
http://www.aqua-medic.com/product/tr.../#!prettyPhoto
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Dimensions: (l x w x h) 5.9 x 2.7 x 2.7 in.
http://www.aquariumhome.ru/images/sh...23/24/7649.jpg
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