New lights and acclimating ??

[Shooter7]

I just switched over from a pair of cheapy reflectors and Reeflux 12k 250w bulbs to a long parallel reflector with two Ushio 10k 250w bulbs and two VHO actinic supplements. Currently, I have the new MH bulbs about 16 inches above the top of the water and the highest coral is probably 10 inches below the surface of the water. I don't have any screens to use on the tank to filter anything out. Can anyone give me some advice on how/when I should lower this lighting so that I don't damage anybody in the tank? And how can I tell if I have lowered them too far too quickly? What kind of things should I look for from my corals? All of my SPS are frags as I'm just getting going with SPS. Tank is a 120g. thanks

 

[fishdoc11]

I have had good luck cutting my photoperiod in half when changing out bulbs and moving it back up an hour a week until I am back at what I started with. Four hours is a good starting point if your photoperiod has been running > 10 hours a day IMO. Also not a bad idea just because you are going up in PAR a bit. Things to watch for are noticeable coral lightening on consecutive days that indicates bleaching IME. If you do notice this slow down or go back down on your photoperiod. Resist the temptaion to move the photoperiod up every 2 or 3 days. It's much better to go too slow than too fast.
hth, Chris

 

[Shooter7]

Thanks Chris. The frags I got from you are still hanging in there. Hoping I can get that ORA blue mille to color back up better for me. I continue to work on keeping my water parameters good. Now, as far as the lights, should I lower the lights down more and then run them shorter photoperiod? Trying to understand where I should have them for proper positioning AND photoperiod. thanks

 

[fishdoc11]

Maybe bring the photoperiod up and then gradually lower the lights. I am not able to move the lights in my main tank so I never adjusted the height but it couldn't hurt IMO

Chris

 

[Shooter7]

Ok....yeah, I have my lights suspended on chains from hooks in the ceiling. I have an open top canopy. This greatly aids in cooling and ease of accessibility to the top of the tank. Any suggestion on what my final height off the water should be for the halides?

 

[fishdoc11]

My fondness of wrasses necessitates me having a closed hood

I like around 8".

Chris

 

[Shooter7]

I have a really tall canopy at 17", but I have some open area on the back and my carpenter's managed to jump out through there. Really loved that fish. I'm going to rig up something so I can get another one.

Thanks for the lighting advice.

 

[fishdoc11]

No problem....good luck