Description Make of high quality ceramic material to produce ultra fine bubbles. Product is export quality with upgraded packaging Suitable for fishes and shrimps. Specifications: Size (mm): 50, 80, 100, 150, 200 Material: ceramic 50mm size: tube diameter 4mm, suitable for fish tank 50-120cm 80mm size: tube diameter 4mm , suitable for fish tank 70-160cm 100mm size: tube diameter 4mm , suitable for fish tank 90-180cm 150mm size: tube diameter 4mm or 8mm, suitable for fish tank 100-200cm 200mm size: tube diameter 4mm or 8mm, suitable for fish tank 1200-2200cm Compatible air pump power: 50mm size: Single output 4W 80mm size: Single output 5W 100mm size: Single output 6W 150mm size: Single output 8W 200mm size: Single output 10W Feature: 1. Soak the product under water for 2 hours earlier before connecting to air pump. 2. Workable with relatively lower power air pump than the conventional nano air stone disc in the market. 3. If tank water is deeper than 40cm, do consider switching to a stronger air pump to increase the performance.