The Lighting Upgrade
In mid 2006, I decided to upgrade my tank lighting as I felt that the 250 watt lamps were not providing a cost effect solution to my lighting needs. Firstly, having six double ended metal halide lamps to replace every nine months was a bit painful to the wallet. Secondly and more importantly, I just wasn't getting the color out of the corals that I knew I could achieve with more intense lighting that favored the blue spectrum. The ultimate solution that I came up with was to remove the four 250 watt 10,000K MH lamps, and replace them with two 400 watt 20,000K MH lamps and four 54 watt actinic T5's.
Four Icecap 400 watt metal halide electronic ballasts.
Four Icecap 250/400 watt DE HQI metal halide pendants
Four Icecap 400 watt 20,000K DE HQI metal halide bulbs
One Icecap 250 watt T5 electronic ballast.
Four Geisemann True Actinic T5 lamps
The Original Canopy with 250 watt Lamps
Removal of the Canopy
After removing the oak canopy, I supported it on some chairs so that I could take measurements, walk around it easily, and position the lighting before I commited to drilling.
Drilling for the Metal Halide pendants
The metal halide pendants were positioned in each of the four quarters of the canopy. I used a combination of eyehooks and springhooks similar to the kind that mountain climbers use in order to make maintenance convenient.
Side Hanging View
The same view as above, but from the side. Since the canopy was supsended on the chairs, it allowed me to do a full mock-up before having to re-install it above the tank.
The requirement was to make both the T5 and Metal Halide lighting hang at the same height so that neither shaded out the other. I used a countersink bit to recess the nuts so that I could achieve this goal as well as create a cleaner finish.
Since the T5 bulbs are long and fragile, I decided to mount them on a board rather than directly to the canopy. The board itself is suspended from the canopy. The center board holds two 54 watt T5 bulbs, and the outer boards hold a single 54 watt T5 bulb.
Center T5 Lighting Mount
The center T5 bulbs were hung from the canopy prior to mounting the metal halide pendants. Since the T5 assembly is a retro-fit kit, the wiring needed to be done in place. It's a source of frustration that there isn't an out of the box quick release kit like the metal halide pendants have. In the future, I may build one myself. Notice the open eye hooks approximately 25% from the left and the right sides. Those open eye hooks will be used to mount the metal halide pendants.
Metal Halide Installation
Notice how the lamps have the same height above the water to avoid any shadowing. The lights also fit snuggly together to avoid any wasted surface area for lighting.
The Finished Product
The final product consists of 1600 watts of 20,000K double-ended HQI lighting and 216 watts of T5 actinic lighting.