A few questions.
Why did you choose not to do an external overflow and save the valuable space inside the tank?
Why did you not drill it for closed loop? It would have a little cleaner look inside the tank without the wires and powerheads on the glass? At the very least could use both.
Why not go with LED technology now?
The money you save not having to use a chiller as much should pay for the lights fixtures. Even if you decide to upgrade later not to mention the bulb replacement cost, and energy savings with LED. You noted Lighting cost is not a concern, and if I am not mistaking there are several threads that show great success with corals and LED lighting. This months CORAL magazine is devoted to LED lighting.
I recently took down my two 215 gallon Oceanic tanks that were plumbed into a central 300 gallon Rubbermaid sump in my garage. I have a Rheem air conditioner and swimming pool heater coil for my chiller. The coil cools the water instead of heating it since I have it set up to cool and not heat. The water in my hot garage plus the heat from my halides. Drove my bill up to $500 in May. If I had not taken them down, my bill would have been close to $1000 for June, July , and August.
That was bad planning on my part. I am thinking of having a tank built 500 + gallons, and put a large sump under it. This way I can just have a 3/4" line running to my chiller heat exchanger in the garage. It would not have to work as hard that way. That coupled with LED technology using less power than metal halides would also help.
