Protein skimmer??

I have seen some comments on a protein skimmer for aquariums on the net,do i need one for our little tank.
I have some live rocks,two nemos and a white bubbly anemoni,had a little blue fish and it disappeared.
I don't know what it was,i was told they are good to start the aquarium.
It is an all in one aquarium,thats what i was told,it must be good the bubbly looks a bright white now,it was just sought of brown when we got it.
What does a protein skimmer do,is it a really good thing?

No one wants to comment Mandy,strange,skimmers are very popular with most marine keepers.
If you want to put a skimmer to your tank you should there is no disadvantage,it is an advantage.

Though not really imortant,if water changes are carried out,you have algae some where in your system and your water movement is braking the surface quite well.

It is quite an indepth thing to go into the explaination of what it does,i will just leave it at that.

skimmers reomve waste from your tank .like what a beach does when you see waves crashing and creating foamy looking surf. you saud your anemone was brown now looks white it sounds like its bleached.it needs good light and feeding to get its colour backyou can feed it thumbnail size uncooked peices of prawn.

and put something around you filter inlet the part where water gets sucked into your filter .or the anemone will get sucked through the filter and your tank will crash and evrything will die and the smell will not be good.

if you have some fly screen just wrap it around the filter and put a few rubber bands on to hold it
in place around the filterany fine mesh netting even a cut a old stocking and just do as as stated above.