Go with a skimmer rated for 1 1/2 or 2 times the actual gallonage your system will have. Remember all skimmer brands overrate their models.
Just DO NOT get a sea clone whatever you do- youll think it looks ok and its cheap but will cost you more in the longrun because youll soon see you need a better one and have to spend on a good one after.
Good luck with your shopping and welcome to the hobby.