Will I need one if i have coral. I am asking because I got mixed answers, someone at the fish store said that if I only have a few fish, and some coral I should be fine. I would really appreciate any help. Thanks.
You never really NEED a skimmer, it just helps in keeping your water parameters at top notch. Dont even bother unless you have the $$$ to buy one that's worthwhile.
This has always been a big debate amongst reefers the world over... wether to use a protein skimmer or not. Good arguments have been stated by both those that agree on using one and those that disagree.
One of the main drawbacks of having a protein skimmer is that skimming not only removes dissolved organics but also can removed dissolved nutrients. So I myself agree with the majority of nano-reefers who believe that regular water changes obviate the need for a skimmer as Musho has already said!
Other drawbacks include skimmer are often quite noisy and a decent worthwile one costs a lot of money. No point getting a cheap one as it is just a waste!
I agree with adrinal, do water changes as often as your system requires them... it all depends on how heavily you stock. An average recommendation is about 10% every week or 15-20% every fortnight! Some people do bigger water changes more often whereas others do smaller less often. All depends on your system!