1/2'' Tubing is the standard tubing used to connect to pumps, 1/2'' connectors, etc. It is flexible and does not kink easily. The 3/4'' tubing is used to connect to 3/4'' pump outlets. Available in translucent blue and solid black. Solid black prevents algae growth. The blue color allows you to see the flow of solution, yet algae growth is reduced. It is available in rolls of 25' and 100' .