If you’re living through a drought, such as the folks in California, then your aquarium may have to go without its regular water changes, which obviously presents issues for captive reefs. Fortunately, your aquarium can live on without one thanks to all of the modern day techniques for nutrient transport and replenishment. If water changes are definitely out of the question, the use of GFO and carbon will help your reef keep some of the unwanted organic material in check. Couple that with the nitrate absorbing abilities of most macroalgae, and you’ve got yourself a system that can work beautifully with minimal water changes. With nutrients in check, the beneficial items can be dosed manually to the system to make sure the corals get all that they need. The only thing you’ll really have to worry about is topping off evaporated water, which is unavoidable for a reef tank.