Do you know how a protein skimmer works?

I have attached a link for you, which explains how a protein skimmer works and also has a few answers for why your protein skimmer has no foam. There are six different possibilities, and one is that your tank may be too new to have organic compounds. Read through those possibilities and try to fix anything you can. Your tank may not be fully cycled yet, especially since you recently added your puffer. I would say your protein skimmer is doing it's job to the best of its ability.

Hope the link helps.
Protein skimmer information

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Phishie
Site Coordinator

"An ounce of prevention is worth a pound of cure."