Nyos Floating Fish Trap:

With conventional traps, catching fish is complicated because a fish-catching mechanism usually needs to be activated via a line. 
With the Nyos® Floating Fish Trap®, however...no line. The fish trap can be attached to the aquarium glass with the magnetic mount. 
This allows for flexible positioning within the aquarium. 
The trap can be placed near the water's surface so that food can be easily added with the included pipette. The Nyos® Floating Fish Trap® is compact and quickly accepted by fish thanks to its round, transparent design. Tips for catching aquarium fish: Fish need time to get used to the trap. As they become accustomed to it, simply feed the fish through the trap. For fish that feed on algae, algae sheets can be attached with the included magnet. The pipette can also be used to keep the food moving. 
Many fish tend to react to food movements. With small, fast-moving fish, wait until they have swum to the trap. Do not use the trap to catch several large fish at once. For shy fish, attach a string to the magnetic holder so it can be released from a distance. For timid fish, remove any dominant fish from the aquarium beforehand. If necessary, turn off the feed so the food remains in the trap.

Designed for glass thicknesses of 8 to 15 mm.