Noobie Filter Question

Hi I just started a 20 gal tank with live sand and rock, and I'm wondering if I should go and purchase a filter of some sort; such as a canister filter or hang on filter with or w/o a bio-wheel. Should I run activated carbon in them while my tank is cycling?

 

For a tank that size, a Fluval 205 canister filter would do the trick, and you could run carbon and biomax or whatever filter media you want in it. There are a lot of brands to choose from, I just say this b/c I'm having good results running a Fluval 305 on my 55 gal.
I have no experience running a hang-on w/ bio wheel, but maybe someone else here can answer about that.

 

I use a fluval 205.
You can hide it nice and easy as opposed to a hangon - i personally also run carbon 24/7, helps keep my tank from being smelly, water is clearer and also it stops chemical warfare!