The Fluval Easy Clean Gravel Cleaner (aka Fluval Easy Vac).

This gravel vaccum cleaner is a practical tool for cleaning and maintaining your aquarium. Its quick-start feature provides a hassle-free startup. An exclusive gravel guard keeps the gravel in the tank, not in the bucket. The oval-shaped cleaning tube allows easy access to corners. Plus, it has a comfortable grip and non-kink hosing.

The gravel cleaner works well in planted and decorated aquariums, and it can be used with the Marina Siphon Starter Bulb

Available in 3 sizes:

Small: the intake pipe is 10 inches long

Medium: the intake pipe is 15 inches long

Large: the intake pipe is 24 inches long

See the Fluval demonstration video

Hagen brand.