If your just concerned about no skimmer for a month, I'd say don't worry at all.
A reef can definately be run without a skimmer, but I'd save that for the more advanced hobbiests. Without a skimmer, it will be all the more important to control nutirent input, and will require some form of nutrient export. A lot of hobbiests have trouble balancing these things WITH a skimmer (the most effective way of pulling nutrients out of a system), so doing it without is a delicate balance to say the lest. Most systems I have heard of that do well without skimming have very prolific algae growth in refugims, cryptic zones, and other ways to keep things in balance.
All that said, if it's just about a month or so, I'd suggest an aggressive water change schedule and you should be fine.
*when/if you do get a skimmer, don't skimp, it's one of the most common things that people skimp on at first and then end up replacing later (so they spend more than if they did it right in the first place).