[lehrens]

I have ordered 400watt MH to upgrade from 175 watt MH, what should I do upon switching lamps? Any acclimation to consider in going to a higher intensity?

[Elmo18]

lehrens,

I'm going to say definitely yes, there will be an acclimating procedure. The 175 MH bulb has a lot les PAR, about 3-3.8 less than Iwasaki 400 MH I believe. Maybe start the 400 MH by putting it higher from the surface of the water. Gradually lower it over time, not in a few days. I would be really concerned with mushrooms and leathers.

I switched my lighting from 2X55 PC's to 2X250 MHs and 2X95 VHO actinics and I had to do it slowly. In fact, i'm still acclimating mine after 2 weeks. I started 5 hours with MH at first high up, and now i'm up to 8 hours. Every thing looks fine and soon I will have the metal halides about 7 inches from the water surface.

Even if the bulbs you are getting are not Iwasaki's there is still a major PAR difference between any 400 MH and 175 MH.

Regards,
Ilham [img]/ubb/smile.gif[/img]

P.s. You'll love the extra lighting!! I love my 250s.

[Ninong]

Lee ~

If you are going from 175w 10,000K metal halides to 400w 10,000K metal halides, you are just about doubling the intensity. If you are going to 400w 6500K Iwasaki metal halides, you are tripling the intensity.

It takes corals in the wild about three weeks to light-adapt to changes in environment that are not nearly as extreme as what you are about to perform with your tank. You are fortunate that your canopy is suspended from the ceiling, which makes it very easy for you to accomodate this acclimation process.

I suggest that you raise your canopy about 10" higher above the tank once the new 400w lamps are in place. Then I would lower it gradually over the next 4 to 6 weeks until it is about 2 inches higher than where you had it with the 175w lamps. You have to be guided by the appearance of the corals themselves, keeping an eye out for any signs of stress and adjusting your schedule accordingly.

Are you getting 400w 10,000K or Iwasakis?

Ninong [img]/ubb/biggrin.gif[/img]

P.S. - Moved to Lighting forum.

------------------
"They want the federal government controlling Social Security like it's some kind of federal program."—George W. Bush, St. Charles, Mo., Nov. 2, 2000

[PerryinCA]

I agree that you will need to be diligent with the acclimation process. Moving the lights higher, and cutting back on photo-period are two good ways to do it.

Here are some threads that should be of interest to you. Doug did the same thing.
http://www.reefland.com/ubb/Archives...16-000902.html
http://www.reefland.com/ubb/Archives...16-000907.html

Good choice, you won't regret it.

-Perry

[lehrens]

Thanks guys, I am going with the 6500 Iwasakis.

[dsb1829]

The upgrade isn't that big of a deal all of my corals have pulled through great. Even the softies and LPS corals that are fairly high in the tank have been able to handle the additional intensity. I am still in the process of acclimating the tank. I think it has been 7 weeks. I had a little bit of a setback when I had a circuit in the appartment go out and ran w/o the MH for three days. I gave it a few days after that to catch back up. I am currently to just under 6 hours a day of MH. I started at 2.5 and have increased it by 15 minutes every 3-4 days. It is a very slow process, but I have had no problems that can be attributed to haste. It is still going to be a few more weeks until I am up to full photoperiod. Just don't rush the acclimation.

Good luck!