Hey, I bought a used reef devil protein skimmer off the forum and the water inlet is siliconed to the tower and it doesn't sound like there are any bio balls in there. Will I need to get some in there for it to properly skim?
Yes, it's normal for downdraft skimmers to have bio balls in the tower. IIRC for the reef devil it needs smaller sized ones that I have only seen in a reef devil, so if it's missing them you might need to contact ETSS to get them, www.superskimmer.com