HOB Aquarium Filter Adjustable Water Flow External Filter – For 5-15 Gallon Tank

Aobosi Induction Hob Single Induction Cooker Portable Ultra-thin RRP £41. --Raising the water level in the aquarium reduces the sound of the waterfall due to the difference in water level. --Adjust to fit (balance) with the wall of the aquarium to reduce noise.

eBay