Aqua Medic Midiflotor Internal protein skimmer for aquaria up to 400 litre (100 Gallons). The Midiflotor is a small but powerful air-driven internal protein skimmer. Like the Miniflotor, the Midiflotor features the double reaction cylinder. Within the inner cylinder, air bubbles rise and carry large quantities of water. This water falls into the external cylinder and carries the air bubbles downward into the expansion cone. Here the bubbles turn, and rise upward into the foam cup, against the strong counter-current. The Midiflotors foam cup inner tube is conical, which ensures quick extrusion into the cup, and helps to dry the foam. The strong holding system allows movement of the skimmer vertically to adjust the foam production zone. A lime wood air stone producing very fine air bubbles is also included. For the air supply, we recommend the membrane air pump Mistral 200. Diameter: 75 mm, c. 3". Length: 40 cm, c. 21". Total width: 15 cm, c. 6".