Let's face it; quiet protein skimmers are a rare breed. One consolation that aquarium enthusiasts tell themselves is that if a skimmer is quiet, then it's not working efficiently. However, there exists several 'hacks' that succeed in turning down its volume.
Place a yoga mat under the sump: Hear us out. If the cabinet holding your protein skimmer acts somewhat like an amplifier, a yoga mat combined with a piece of neoprene will work a charm.
Invest in an air silencer: An air silencer effectively muffles the noise of incoming air – and it's a sought-after item in this day and age, given that the average air flow rate of protein skimmers is rapidly increasing. It's important to note that if the air silencer on your protein skimmer isn't working, take your skimmer apart and check for salt build up that impedes noise obstruction.