When our experiment was over, we decided to try out this instant nitrate reduction water change method that had been contemplated for some time. Performing the water change method shown in the animated graphic below, we reduced our nitrates quickly to zero with no ill or harmful effects to any of our established aquarium residents; a 15" Snowflake Eel, some various types of hermit crabs and snails, a few crabs, two colonies of Zoanthid, some non-living corals, and some live rock.
The behavior of the tank inhabitants improved greatly afterward as well. They became more active, started eating better, and had brighter colors within a few days. We even added a new mated pair of Coral Banded Shrimps the day after completion of the water change procedure, with no problems at all.
One important consideration before you start a massive (or any, for that matter) water change is to remember that you will also be changing the pH in your tank (probably upwards). Before beginning a water change, it is wise to slowly adjust your tank water pH to where it will be when you are finished. This will prevent your tank critter from going through "pH shock", which can be fatal to more sensitive tank critters.
Prior to beginning your water change, you can adjust the pH upward with common baking soda, or downward with one of the many products on the market to reduce the pH of aquarium water.
