The Fluval A807 is the correct air pump for the following tank sizes:
The Elite Optima Aquarium Air Pump W/ Rheostat- 30 Gal provides increased pressure and output for tanks up to 30 gallons in size. The Optima air pump provides power for air stones and internal and undergravel filters, and also includes a single outlet with Rheostat control. This 110 volt high power air pump agitates water surfaces and improves oxygenation.
Elite Optima Aquarium Air Pump W/ Rheostat- 30 Gal specifications: