A jump from PC's To 175 Mh 10000


New member
So i took the leap and bought a MH fixture from someone dirt cheap its a Hamilton 175 mh and 2 vho bulbs 48 inchs One of the bulbs works I ordered the other bulb . What kind of time should I leave the one mh bulb on for. Keep in mind i jumped from pcs to the metal halides. Also its a 55 gallon long tank.


New member
Its not so much a time issue, but rather an intensity issue. Some raise the lights above the aquarium and slowly bring them down. Others use multiple screens and remove them over time. I would still run the lights 6-8 hours during this time.


New member
the lights should work independently, I would have the VHO (2 actinic would be ideal) come on first for 2 hours, then the MH after that, then have the 2 actinics on 2 hours after the MH shuts off. The MH will add heat to your tank as well. OnlyCrimson is right the intensity will be huge compared to the PC's so you will have to acclimate your corals to the light. Best option is the screen. Put 3-5 layers of screen over the tank to act as a filter, and remove 1 screen a week until they are gone. You don't want to run the risk of burning your corals. Good luck! Hope this helps.