A CPR BakPak will work quite nicely. Koralia 3's have 850gph I think. My 20g has 2 koralia 1's and a maxijet 1200 powering my skimmer. Total of about 1100gph, in other words, I have 55x turnover per hour in my tank.
as for the power heads i am not to sure but that first skimmer is a def no!!! it looks like the sea clone which was a piece of crap no one likes it as for the second skimmer i have heard good things about it i want to try it in the future my local petland sells that one
I have a seaclone.....It's not all bad, it just takes forever to adjust it. Still I agree the seaclone is junk. I just didn't feel like taking it back.
Do you think it wise to buy a used protein skimmer? Theres a nice CPR bak-pak for 50$ thats Used-Like New.. and im trying to save A BIT of money lol. If not it doesnt matter, theres a new one for 50$ more, but still. Is used ok or i shouldnt do it?