EHEIM Quick Vac Pro

With this battery-operated sludge vacuum, you can clean your aquarium’s substrate conveniently and independently of water changes. The device’s performance is tuned to pick up debris without disturbing the substrate excessively. A filter container within the device retains the debris and immediately redirects the water back into the aquarium. Removing the filter element is very easy.
For cleaning the substrate in between (independent of water change intervals)
The ground is hardly disturbed
Water flows back into the aquarium
Batteries included