Python Pro Clean Gravel Washer & Siphon Kit with Squeeze Pro-Clean Gravel Tube Length Gravel Tube Diameter Overall length Recommended for Large 16 Inch 2 Inch 6 Feet Most tanks 50 gallons and up Medium 10 Inch 2 Inch 6 Feet Most tanks 10 gallons and up Python Pro Clean Gravel Washer & Siphon Kit without Squeeze Pro-Clean Gravel Wash Gravel Tube Length Gravel Tube Diameter Overall length Recommended for 1" Small Tall 20 Inch 1 Inch 6 Feet Tall nano tanks 1" Small 12 Inch 1 Inch 6 Feet Nano tanks up to 30 gallons 1" Mini 6 Inch 1 Inch 6 Feet Small fish tanks and fish bowls under 10 gallons 2" XL 24 Inch 2 Inch 6 Feet Tall, large tanks 2" Large 16 Inch 2 Inch 6 Feet Most tanks 30 gallons and larger 2" Medium 10 Inch 2 Inch 6 Feet Shallow tanks 30 gallons and larger