LED Photon 48W Lighting Help

[therealkilo]

I am still having some issues dialing in my LED lighting. Can anyone please advise...

Lighting: Reef Breeders Photon 48W

Tank: 55 gallon tank. L=48" x D=13" x H=21"

Lights are on tank mounts 6" from top/lip.

I've done the slow ramp (5%) using the excel document and this is my current lighting schedule:

0 18 36 50 61 69 71 69 61 50 36 18 0
0 13 26 36 44 49 51 49 44 36 26 13 0

Issues:
Have some brown algae growth.


10-12" From Top:
Favias - aren't looking too good (white / brown).

Forest Fire Digi - not looking too good. Patchy.

Green Porcillopora - doing very well. Growing like weeds.

Montipora Capricornis - have died it seems.


Bottom 6" of Tank:
Umbrella leathers - doing very well. Multiple locations in bottom of tank.

Green star polyps - doing very well. Multiple locations in bottom of tank.

Button Polyps - doing very well. Multiple locations in bottom of tank.

Pulsing Xenia - doing very well. Multiple locations in bottom of tank.

Torch - doing very well. Multiple locations in bottom of tank.



Any words are appreciated.
Thanks!

[Percula9]

Are the numbers you listed in percentages? If the corals that are doing bad are high in the tank then put them on the bottom.The light might be to much for them.Some times it takes time for corals to acclimate to led.Can you give me the specifics of the light?

[steallife904]

think u are running the white channel to high.

[therealkilo]

Yes, sorry the light amounts are in percentages. Top #'s are blue followed by white on the bottom.

The specifics of the light are: Reef Breeders Photon 48W with 90 degree optics. Mounted 6-7" off the top of the tank. About 8-9" of the water line give or take.

[Ron Reefman]

How long have you been using this fixture and what did you have before?

I don't think you are running anything too high... unless this is new and you are switching from a t5 fixture. Then you may need to dial it back some and do some acclimating.

My concern is the limited amount of time you have higher values of power on for. It takes a good level of PAR for photosynthesis to start and it takes an hour to ramp up. If 50% is enough, you are OK. If you need 60%, then you are shaky. If you need 70%, you don't have enough. I have a similar fixture, EverGrow IT2080 (EG makes the RB Photon) and over a 24" deep tank I run 90% blue and 40% white for 4 hours and fairly high numbers for 2 hour before and 2 hours after. And although my tank is deeper, I have sps and lps corals withing 10" of the water surface.

[therealkilo]

Ron. Everything is new to the tank, lighting included. Tank has been running for about 9 months. All coral and other inhabitants are about 1-3 months in.

I think you are right about the length of time on lighting schedule. So typically, I should be running 4hr constant then the 2 before and after ramping down?

[therealkilo]

What do you think about this?

Blues are top numbers
30 36 42 58 62 71 71 71 71 62 58 42 30
15 20 28 40 40 46 46 46 46 40 40 28 15

[Ron Reefman]

I don't think there is anything special about the 4 hour and 2 hour before and after, you could just do 3 hours up at high PAR levels and 3 hours back down so there is enough light for photosynthesis. Or just 6 hours at the peak.

Your schedule looks fine. If you can, fine somebody with a PAR meter, that's the best data you can get. Otherwise I suggest the 'canary in the coalmine coral'. Take an inexpensive frag of a Monti and set it as high as any coral in your system. Then keep bumping up the power levels until that monti frag bleaches. Then you know you are at the high end of the light the rest of your corals can tolerate.