wet vs dry skimming aside, I agree that water changes are not nearly as important for lightly stocked tanks as they are for fully stocked tanks. I have a 6.5 year old tank thats never had a water change and other than a sickly acro frag i placed in it, all the corals and both my fish have been uber-happy (scientific term in Montana) for almost 7 years. Of course I did lightly randomly does stuff like a really old 20th century bottle of 'essential elements' (i threw it out a few months back) and much to my own dismay I put a bit of purple up in there that wouldn't hit my SPS tank EVER. Point is Overstock, alot of people on this forum are rightly enraged when people blatantly abuse their specimen, whether is coral, but especially fish. Without more information on your system I can't say you are placing your little guys in a bad situation, but it sounds that way from what i've read.