a question about protein skimmers

Depends on the tank size and the power of the skimmer. One should be enough especially in a reef set-up since you dont want to take all the goodies for the corals out of the tank.
 
I'd look at the type of protien skimmer and the quality before considering how many to have. Example, a hang on back, or in-sump, etc. for type, and as for quality, the brand, like AquaC Remora (which makes a very good HOB skimmer). Also, maybe rather than having more than one, just get one that is rated for a bigger tank than what you have. That's good too because if you decide to upgrade your tank later you won't necessarily have to replace the protien skimmer. Cheers! :D
 
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