Does it make sense to tear down a thriving, healthy reef tank? On the surface it would seem to be a foolish move but a tank with too much coral growth can spell trouble. Growing corals can cause a drop in circulation and make it easier for detritus to settle inside a tank. This can lead to problematic algae such as cyanobacteria. Less circulation will also make it harder to deliver nutrients to corals.
This was the scenario I experienced with my 187 gallon SPS dominant tank. It was started about five years ago and certain colonies were taking over a lot of real estate, crowding and shading out other corals. Some cyanobacteria was present, although it was at a manageable level.
Tank at Crossroads
Repeated fragging worked for a while but it became less and less effective over time. Some corals were succumbing to Slow Tissue Necrosis (STN) at or near their bases due to a lack of light and flow. The tank was at a crossroads and I couldn’t believe I was contemplating a re-do of this gorgeous reef.