OASE CrystalSkim innovative aquarium surface skimmer quickly and effectively frees the aquarium surface of biofilm, floating plant debris and substances. CrystalSkim is compact in size and has a powerful and quiet motor. The flow is adjustable, ensuring a crystal-clear water surface at just the right output. An integrated collection basket ensures the safety of the aquarium inhabitants. In addition to skimming, the unit is designed with a bottom discharge that creates flow in what would be dead spots normally.