Hi there. If you are doing an all-in-one type of tank, I wouldn't worry about a skimmer (most skimmers for AIO's won't fit or are overpriced). If you're going to run a sump, its not a necessity, but something you could get down the line if there's room in the budget. I like the idea of simplifying our tanks, so in future builds I will likely go skimmerless. Keep us posted on the new tank!