I have a 90 gallon fish/coral tank that I just added a 48" Current light system with the 150 W Metal Halides. I have never used Halides, and am seeing an almost instantaneous effect especially on my Duncan Coral. However I notice my water temperature has increased a few degrees. So I turned down my heater, and turned off the Halides until the temperature comes down, however I know I need to fix the issue. Can I get advice from the experts out there how to remedy this. Also I am really looking forward to adding more variety of corals, and also would like some suggestions.