For those of you interested in how my venture in DIY MH turned out, here it is. Find the original thread
here.
Here's my tank with both 250W Iwasaki 6500K MH and 2 110W VHO actinics:
Here's a shot of the outside of the new hood I built to house the MH:
Here is a shot of the workings of the hood:
Here's an Acropora sp. happy to finally get some "real" light:
Surprisingly, the coral who seems happiest about the new lighting is my frogspawn. It has expanded at least 50% more under the MH:
I hooked everything up Saturday and started with a photoperiod of 3 hours each. I plan on adding 15 minutes every other day until I get to a total of 8 hours. I actually didn't expect things to like the MH so much. I was really expecting corals to wither for awhile as they got used to the extra light. They seem to be taking it well. In fact every single one of my corals looks as good or better than they did under VHO. That includes polyps and mushrooms. The bulbs haven't broken in yet, but the overall color is still very pleasing. I would call it "crisp white". Definitely much less blue than my VHO, but where they gave my family room an overall purple glow, it now has a bluish white glow. Looking at the tank now, it just looks really bright. I'm very glad I went to MH. I only wish I would have done it sooner.
As for the $23 ballasts, they get warm but not really hot in 3 hours. They fire up the bulbs right away every time. I highly recommend them as a cheap DIY option. Someday I might replace them with Icecap ballasts, but not anytime soon. I'm also glad to have better access to the tank with the new hood. I took some ques from Playfair's hood with the flip up front design. It affords much better access than my other hood which required me to reach in over the top.
Anyway, I really like the setup. If anybody has any questions, feel free to fire away!
Brian