Googling "Water Changes In Reef Aquaria by Randy holmes Farley" gets the article. Heres a clip from it.
What this article does provide, however, is a clarified understanding of what water changes are capable of achieving. Using known or calculated rates of addition and depletion of a variety of chemicals in seawater, the effects of water changes can be readily modeled. The impact of water changes on calcium, alkalinity, magnesium, nitrate and sulfate, for example, are shown graphically. In several cases, these examples also serve to provide guidance as to what is occurring with other ions not modeled, but which would increase or decrease in a similar fashion. For example, the control of nitrate accumulation with and without water changes can also show what effect water changes have on other accumulating generic chemicals such as phosphate, organics, heavy metals, and other materials.
How much water must be changed depends entirely on what the desired outcome of the water change actually is. If it is to reduce an accidentally added toxin, massive, immediate and repeated water changes may be appropriate. If it is to maintain calcium and alkalinity, large daily water changes may be necessary. If it is to keep slowly added or depleted ions (e.g., magnesium or strontium) from drifting away from "normal" levels, then smaller changes may be adequate.
Previous articles on water changes have "shown" that small water changes are not useful, and have sometimes left the impression that even many small water changes are not beneficial. It is also "common knowledge" among many reef aquarists that continuous water changes (where water is added and removed at the same time, usually by automatic pumping) is not very useful "because this removes some of the new water that was just added." As I'll show, these assumptions do not stand up to analysis for typical water change scenarios. Consequently, whether choosing to change a lot of water, or only a little, and whether it is done continually, daily, or only rarely, more water change options are available to aquarists than many realize. These increased options' availability may permit busy aquarists to spend time on other important activities, and less time on water changes, while still accomplishing the same goals.
Read the entire article. It is verry informative.