Sicce's Shark Pro 500 Internal Filter is rated for tanks up to 37 gallons. It is a fantastic internal filter for smaller tanks that includes a magnetic mount, flow regulation and 3 types of flow options. These are uni-directional flow, an integrated spray bar or an airline that allows for oxygenation from the uni-directional flow outlet.
You can add multiple modules to the filter through their 'magnet connecting system' that allows for more filtration in larger tanks.
