I've been struggling with the same question. IMHO, the stock setup is no where near ideal for SPS. I assume a better ballast would provide more light, but even then, I think more than 150 watts of MH is needed. I'm planning a larger (150 gal) tank and I didn't want to spend a fortune on upgrading lights on this one. I've been researching a few options...
- The new dimmable Lumatek ballast that adjusts to 150, 175 or 250 watts. This would allow for the over-driving of the current bulb/hood (the current hood is only rated for 250 watts total.) or;
- A new hood - I like the cheap Odyssea option w/ 250 MH ($169) but many complain about those ballasts and it uses PCs for the actinics. By the time you upgrade the ballast and bulbs, you've spent nearly as much as a higher quality setup.
In the end, I decided to "bite the bullet" and ordered the updated AquaIllumination (
http://www.aquaillumination.com/) LEDS through ReefGeek. They are insanely expensive, BUT can easily scale up for the larger tank. Depending on if you believe the light output projections, two of the AI units at max with the new Cree XP-G LEDs will provide the equivalent of more than 500 watts of MH with infinite color control and almost no heat transfer to the tank.
Eliminating the heat from the main MH allows me to move forward with my design to create a frag tank in the center sump section using this
http://www.nanotuners.com/product_info.php?cPath=74&products_id=623
450+ 1200K PAR from a 21 watt LED light! :dance:
Skimmer update - Today is day 3 with the new Bubbble Magnus skimmer and it's starting to produce. Even though it's still breaking in, it's already out-performing the stock unit.