skimmer mandatory?

[reefnoob]

I have a 90 gallon tank and was wondering if I need a skimmer. What does a skimmer do, and do I really need one? If I need one, what kind would you suggest?

 

[stiracerdude]

I would read this article Aquarium Filtration & Water Quality: Maintaining a Healthy Saltwater Aquarium with Protein Skimmers

 

[little_fish]

On a large tank they really help keep the dissolved organics out of the water, keeping up your water quality. However, you dont really need one if you are diligent about frequent water changes and keep your stocking list low

 

[Bifferwine]

Not mandatory... But definitely helpful and most people wouldn't go without one on a 90 gallon tank.

What kind you should get mainly depends on whether you have a sump or not. There are two main types of skimmers -- in sump, and hang on back. If you don't have a sump, you will need to get a hang on back (HOB) skimmer.