I just upgraded My innovative marine 20 gallon to a 60 gallon can I use my midsize protein skimmer with magnets holding it up or do I have to get a new protein skimmer
Doesn't hurt to try. I ran a skimmerless tank for a long time without issues. If you're the sort that likes heavy skimming it'll probably be a little weak, but since you already have it I'd encourage you to give it a shot if you're unsure.