How low is too low

[AdamSabina]

I am experiencing some bleaching of new corals. My lights are 200ish par at the area I put my acros and 70ish on the sand bed. The system the came from was 250-300par. So I placed them semi high up.

The issue (I think) is my organics. I run 1/3 cup of bio pellets on my 150 gallon. My bio load is light. My NO3 is 2ppm and phosphates are undetectable on my Hanna checker.

 

[Koralcrazy]

what lights are you running and what lights did they corals come from?

Metal halide 200 PAR is very different from LED 200 PAR...

In short, you want about 30-40% less par if you are running LED, if the corals came from metal halide....

 

[Reefer54]

par is one thing....spectrum and kelvin are another...though closely related.

you may need to consider what lights they came from to what you have,

what about params and flow

 

[Reefer54]

Metal halide 200 PAR is very different from LED 200 PAR...

In short, you want about 30-40% less par if you are running LED, if the corals came from metal halide....

Just curious how or where this info came from...is this personal experience or do you have literature to base it.....i think this issue is something that needs to be addressed more often as the tchnology is changing and you hear about so many that are bleaching corals with leds.

i use 2 165w 20k led full spectrum lights over my 75g and have 1 at 1 height and 1 at a lower height, but both run 100% white and 100%blue. i am considering lowering the whites a bit as some sps take longer than i like to acclimate. top positioning par for me is just about 300-350, with max par at surface at 412.

i dont mean to hijack, but i think it relates

 

[Arkayology]

How long have they been in your tank for the bleaching to occur? It may be a combo of lighting and lack of nutrients.

 

[Dog boy Dave]

I am experiencing some bleaching of new corals. My lights are 200ish par at the area I put my acros and 70ish on the sand bed. The system the came from was 250-300par. So I placed them semi high up.

The issue (I think) is my organics. I run 1/3 cup of bio pellets on my 150 gallon. My bio load is light. My NO3 is 2ppm and phosphates are undetectable on my Hanna checker.

I agree with you here. Its your organics, not the lights. Granted, bright lights can bleach a coral but coral are remarkably adaptable when it comes to light intensity in a higher nutrient tank. I have several zones in my system. Some are lit very bright and some zones not so bright. I have halides, several types of leds, and t5s. 4 tanks all plumbed together, over 800 gallons and I move corals around quite freely. Even if a coral prefers lower light and some do, i seldom see a coral severely stressed if I move them to brighter lights UNLESS THERE IS ANOTHER ISSUE. Even if your lights are causing the color loss, you would most likely see better results if you raise your organics a bit.

 

[Dog boy Dave]

Just curious how or where this info came from...is this personal experience or do you have literature to base it.....i think this issue is something that needs to be addressed more often as the tchnology is changing and you hear about so many that are bleaching corals with leds.

i use 2 165w 20k led full spectrum lights over my 75g and have 1 at 1 height and 1 at a lower height, but both run 100% white and 100%blue. i am considering lowering the whites a bit as some sps take longer than i like to acclimate. top positioning par for me is just about 300-350, with max par at surface at 412.

i dont mean to hijack, but i think it relates

I would agree with the poster regarding the LED level of intensity. about 19 months ago, I changed my main display which is a 60 inch by 48 inch 27 inch deep cube. I was running 6 times 400 watt halides about 6 inches above the water. Some of the corals were growing out of the water right under a 400 watt lamp. This is a hi nutrient system and most considered it brightly lit. I removed the halides and replaced them with home made LED lights. They were also very bright but they didn't look as bright as the halides. Over the next 9 months, I dealt with several light stress issues, including some color loss on certain corals. After i reduced the gain on the white light drivers, I saw improvement. In additions I saw the corals that were unhappy under the extra white react more dramatically to stress issues if I had an external stress related incident.
Over the years my observations lead me to believe that corals are more sensitive to light issues if they are being stressed by some other factor. I also have seen that corals in a higher nutrient tank can deal with much higher light intensity than those in a lower nutrient system.
I am also often surprised at how well some sps do when i move them out of main system into another place that receives different or lower intensity lights. Even with all the same water the color variation is amazing. The corals themselves are remarkably adaptable to light intensity and color. I find them to be much more sensitive to chemistry changes.

 

[Reefer54]

I would agree with the poster regarding the LED level of intensity. about 19 months ago, I changed my main display which is a 60 inch by 48 inch 27 inch deep cube. I was running 6 times 400 watt halides about 6 inches above the water. Some of the corals were growing out of the water right under a 400 watt lamp. This is a hi nutrient system and most considered it brightly lit. I removed the halides and replaced them with home made LED lights. They were also very bright but they didn't look as bright as the halides. Over the next 9 months, I dealt with several light stress issues, including some color loss on certain corals. After i reduced the gain on the white light drivers, I saw improvement. In additions I saw the corals that were unhappy under the extra white react more dramatically to stress issues if I had an external stress related incident.
Over the years my observations lead me to believe that corals are more sensitive to light issues if they are being stressed by some other factor. I also have seen that corals in a higher nutrient tank can deal with much higher light intensity than those in a lower nutrient system.
I am also often surprised at how well some sps do when i move them out of main system into another place that receives different or lower intensity lights. Even with all the same water the color variation is amazing. The corals themselves are remarkably adaptable to light intensity and color. I find them to be much more sensitive to chemistry changes.

I agree with you 100% about stress being exponential when there are multiple factors. I am just curious where the percentage of down-ramping the lights came from. thanks for the sresponse, experience talk and ideas walk, but to have some sort of equation or known percentage to work with when adjusting the par levels would benefit many I think....and I know that not all leds are created equal, as well as the custom diy setup, but a good basis to gear the adjustment on would be abeneficial bit of info. imo. thanks again.

 

[AdamSabina]

How long have they been in your tank for the bleaching to occur? It may be a combo of lighting and lack of nutrients.

They seem to bleach over 2 weeks. The lights I'm using are 120watt Chinese LED probably 22k equivilant. They are 16" off the water line.





View attachment 253125

Both of these pieces started bleach 2 weeks after acclimation. Anyone keep SPS with success at my nutrient level?

 

[AdamSabina]

I agree with you here. Its your organics, not the lights. Granted, bright lights can bleach a coral but coral are remarkably adaptable when it comes to light intensity in a higher nutrient tank. I have several zones in my system. Some are lit very bright and some zones not so bright. I have halides, several types of leds, and t5s. 4 tanks all plumbed together, over 800 gallons and I move corals around quite freely. Even if a coral prefers lower light and some do, i seldom see a coral severely stressed if I move them to brighter lights UNLESS THERE IS ANOTHER ISSUE. Even if your lights are causing the color loss, you would most likely see better results if you raise your organics a bit.

Should I remove pellets 1/6 cup or increase feeding. Maybe coral food?

 

[Arkayology]

Should I remove pellets 1/6 cup or increase feeding. Maybe coral food?

You could do that. You could also add some more fish.

 

[AdamSabina]

You could do that. You could also add some more fish.

I like that idea better. The slow part is getting everything through quarantine.

 

[Reefer54]

Its the spectrum of light...id bet my tank on it.

 

[ssscuz]

Its the spectrum of light...id bet my tank on it.

Agreed, the cheap light may not have the spectrum that type of coral needs.
Par over 600 on a mates tank and he never bleached anything. My tanks up over 450 on most sps.

What about all have u had any swings? Or low calcium lately?

 

[Reefer54]

Par is great, but pur is better and more applicable when talking about what corals need.

 

[AdamSabina]

Think I solved (or a least I hope I did) this issue. The store was nice enough to trade me pieces and I placed it in a MUCH lower light area and it's doing great. I've had it he new piece for 3 week and it has great color and polip extension.

 

[Reefer54]

glad to hear it...