Space in the coral troughs is always at a premium at the ReefGen coral farm, and we all agree that water flow is one of the most important aspects of coral care. When one of my troughs has an area of inadequate flow, such as this Acropora grow out system, it starts under-producing. I needed to build a unique surge device to provide more flow to the stagnant corner, as well as create a chaotic alternating current for the Acropora located downstream.
Extra horizontal space is hard to find, even outside the troughs, but I had an abundance of vertical space. To make the most of what was available, I had to get creative. I constructed the main body of the surge reservoir out of 3 inch pipe, and used a 3 inch T with a 1 inch side outlet. I then glued 1 inch pipe and a 90 degree elbow inside the T fitting that connects towards the bottom of the reservoir. I have a siphon break at the bottom of the pipe, this airline then feeds into the top of the one inch pipe outlet, and finally, exits the T fitting. The siphon break also feeds into the end of the outlet on the side of the tank. This allows enough air into the pipe to break the siphon without feeding excessive air into the water flowing from the unit.
I added a safety overflow drain at the top to prevent any flooding in the case of blockages or problems with the water flow out of the unit. I located the inlet of the pump feeding the unit at an inch below the water surface. If there are two simultaneous failures – a lack of flow from the main feed pump into the trough and a malfunction of the surge, the water level will remain high enough to keep the coral submerged. Just two weeks later, the coral in the path of the surge are happier and growing well. Happy reefing!