Struggling with LED lighting

[HWDylan]

I have a 75 gallon DT that I built a DIY LED light for from Rapid LED.

I am having problems with corals keeping their colors after I put them in my tank and since I have nearly exhausted all other options (i.e. nutrients, cal/alk, etc) I am left thinking that maybe it is my lighting that is giving me troubles.

I have tried to get advice from several places and I get a HUGE range of opinions regarding my lights. I have heard I have too much, I have hear that I have no where near enough, I have been told to dim them, raise them, lower the time they are on, and everything in between. I want to know what you guys in the lighting dept think.

Like I said, my tank is 75 gallons 48"x18"x21". My lights are the 75 gallon retrofit kit that Rapid LED sells This one. I have since added 12 more LEDs to the fixture to kind of round out the spectrum and bring the total number of LEDs in the fixture up to 60. I have the whites on a dimmer and the blues on a dimmer but the color channel (UV,red, green) is non-dimmable.

I am currently running everything at 100% because the LFS I buy from have everything under radions that run at 100% for several hours a day so I am trying to mimic what they are doing because everything looks great in the store but loses color in about a week in my tank.

My lights are 8.5" from the surface of the water and all my LEDs have 80 degree optics on them.

I want to use a PAR meter and really find out what my lights are doing but they are so expensive and I cant find anyone around here that has one I can rent or borrow.

I'd love to hear what you guys think the problem is.

 

[Zero Nitrates]

Maybe try dimming the whites to 80% and leaving the blues at 100%. It should make the colors pop.

 

[Dana]

I would dim them. What have you got to lose trying?

 

[Eric B]

I run led's with 60 degree lenses on blues and whites only and I also have uv's/red's/green's in each fixture (When all fully on it is about 10-12K look as I hate the mostly blue look). The fixtures are run at 100% all the time and there are 7 over a marine land 300DD tank. I always when receiving a coral from another tank no matter what type of light it is on goes on my frag rack that is near the bottom 1/3 of the tank then week by week I raise them up slowly until they are about the level I will mount them in the tank. I them permanently mount them in the spot I choose and they all seem to do great. I think they need a chance to get use to the new/different lighting and your tank conditions and I have had stuff color up better than under tanks they came out of with mh over it. I do this even if frags come from a tank with far more powerful lighting then mine and all are growing like crazy!

 

[HWDylan]

Noted. I will do that in the future for sure. I actually have a reverse prism favia frag I bought sitting at the bottom right now that I plan to move up a bit in a week. As for the corals I have now, you think they will get it together and color up or so I need to lower them let them get adjusted and them start moving them up slowly? They are all growing good, they just lost the really pretty colors they had in the store.

 

[reid429]

Holy hell your cooking at 100% those cool whites will bleach everything in a heart beat. I would put the lights at 50-30 for a good while. 3 watt Crees or bridgeluxe are powerful

 

[HWDylan]

How long should I wait to see if they start coloring back up? Is that something that I will be able to detect in a week or two?

 

[johnanddawn]

You could also try adjusting the lighting schedule
I don't have dimmers so I use timers to create a natural lighting schedule that is bluer most of the day and ramps up. All the whites are only on for a very short time at midday

My suggestion would be to try this:
run your blue channel for 12 hours
Your whites for only about 3 - 4 hours during mid day for a high noon effect
I don't know about the color channel but I would maybe just run that with the whites

Depending on the type of coral it could be weeks to months (sps take a long time sometimes) to see the change

 

[HWDylan]

So do you guys agree that I am hitting them with too much light?

I have some nice SPS in the tank and I do not want to kill them from lack of light.

 

[johnanddawn]

Sps shouldn't die from a little less light - if they do you have something else wrong. You can always run your noon day timers a little longer as they acclimate
I have a bunch of sps too and this light schedule works for me
Try it...

 

[blufin]

try hitting up jedimasterben. He's on this forum and is very knowledgable when it comes to LED's.
Good luck.

 

[HWDylan]

I dialed my whites back from 7 hours to 5 and I dimmed them a little as well. We will see how this goes I guess. Tank looks a bit dim now though to be honest.

I have the blues on 100% for 10 hours. Colors are on 100% for 8 hours and the whites are on for 5 hours. Hopefully things pick up a bit.

 

[Dana]

I think you could dim blues and colors to like 60 or 70 to start and run the whites at 30-40 for 4 hours to start. Jmtc

 

[reid429]

It's gonna take a month or so for it to recover. Take the blue off 100 as well. If you like your tank more blue I would lower the light to 60 blue 40 white or 50-30 for a week or so. Your corals need to be acclimated to the light but man 100% on both will just kill everything. I would run the lights no more than 8 hours anyways. People go all crazy for light schedules but you gotta remember the sun isn't 8" off the ocean water.

 

[Dana]

If there's one thing I e learned, is that reef keeping is slightly different for all of us. What is working for one persons environment may not work for another's. It's kinda funny like that, but these are delicate systems we are keeping.

 

[Ron Reefman]

try hitting up jedimasterben. He's on this forum and is very knowledgable when it comes to LED's.
Good luck.

+1
I'd really like to hear what jedimasterben has to say about this situation. I'm kind of surprised he hasn't already jumped in here. 60 Cree leds over a 4' long, 75g, 2' deep tank doesn't sound like too much light to me. If somebody said they were going to put 1 RB Photon 16 or 24 over a 75g tank everybody would be telling him that's not going to cover the tank. I'd also like the OP to get a PAR meter somewhere. They are a lot more common than they used to be. Even a cheap one from Seneye is better than nothing!

But I use all Bridgelux leds and have never used Crees... that I know of... I had an Eco Tech Radion for 6 months and I don't even know what kind of leds they use? It was a good light, just a PITA to change setting and it ran hotter than I wanted so I sold it. And I have 98 Bridgelux leds over my 55g tank and run them close to 80%, and 198 Bridgelux leds over my 180g tank and run them at about 70% due to much less depth from a big rock wall. And I haven't bleached out a single coral, even in shallower water.

 

[Ron Reefman]

It's gonna take a month or so for it to recover. Take the blue off 100 as well. If you like your tank more blue I would lower the light to 60 blue 40 white or 50-30 for a week or so. Your corals need to be acclimated to the light but man 100% on both will just kill everything. I would run the lights no more than 8 hours anyways. People go all crazy for light schedules but you gotta remember the sun isn't 8" off the ocean water.

PAR for the sun is about 1800-2000 at noon and the PAR values fall off before and after noon (about 1200 at 9am and 3pm). My leds read 2000 PAR at about 1 inch and 1100-1200 at 8 inches. So at the water surface the noon sun is considerably brighter than our most of our led lights, and actually brighter than our lights from about 9am until 3pm. Just thought you'd like to know. Info is from Apogee, who makes the PAR meters most of us probably use.

 

[johnanddawn]

PAR for the sun is about 1800-2000 at noon and the PAR values fall off before and after noon (about 1200 at 9am and 3pm). My leds read 2000 PAR at about 1 inch and 1100-1200 at 8 inches. So at the water surface the noon sun is considerably brighter than our most of our led lights, and actually brighter than our lights from about 9am until 3pm. Just thought you'd like to know. Info is from Apogee, who makes the PAR meters most of us probably use.

I agree - i don't think it is intensity as much as duration is what I was trying to say.
I think that corals like a blast of light but the duration should be short. A 3 - 4 hour blast mid day is enough for most corals to reach photo saturation.

On a real reef the sun moves, shadows are created, different angles of incidence create more or less reflection off the waters surface, waves refract the light into different and diffuse directions, and in effect the coral may only receive that full sun for a very small part of the day. The rest of the time it gets diffuse or reflected light. Imagine a coral on the side of a bommie - most of the day the suns direct light is not getting to it, but for a short window of time the light rays hit it directly, and then its back to being diffuse.

Aquariums are not like this - the shadows do not move because the lights do not move. There is some rippling created at the surface if you have good flow but nothing like a wave going over the reef. One way we can imitate the effect to some degree by ramping up and down are lighting systems and keeping the full blast to a very low time.

Jmo of course...

 

[johnanddawn]

I just did a search on photo saturation and found this article by Dana Riddle that speaks about exactly what I was saying

Feature Article: How Much Light?! Analyses of Selected Shallow Water Invertebrates' Light Requirements ? Advanced Aquarist | Aquarist Magazine and Blog

So I guess it's not jmo

 

[HWDylan]

So maybe keep them at 80-100% and just decrease the time the whites are on? Whites are the ones putting out the big PAR numbers right? or Should I decrease the lighting for the whole fixture?