SPS Bleaching -Need Radion Light Setting Help

[Jackooze]

I am trying to understand the relationship between the orange bar (brightness) on the left-hand side and intensity percentage when hovering over a point on the schedule.
My lights are 8" from water level at 100% brightness using XR15's Gen3 SPS AB+ setting. The depth of the tank is 18" from water level to sand. When I read threads online, does everyone discuss percentages in brightness or highest intensity point on the schedule? Is my brightness to high for my tank?
I have no luck with maintaining SPS corals like Acropora which I keep experiencing them bleaching/browning. My parameters are almost ideal except phosphate that has been fluctuating between .058 - .208. So I can just assume its either the lights or phosphate.

 

[Robink]

I would turn down the lights. I have the radion gen4 xr30's about 10 to 11 inches above the water at 70% , which is the orange bar on the left. this translates to 47% on my schedule. The tank is also 24 inches deep. I would turn your lights down to maybe 50 to 55% and gradually turn them up till you find the sweet spot. Every tank is different. Btw my phosphates are 0.37
I also run the sps ab+ schedule.

 

[Jackooze]

I would turn down the lights. I have the radion gen4 xr30's about 10 to 11 inches above the water at 70% , which is the orange bar on the left. this translates to 47% on my schedule. The tank is also 24 inches deep. I would turn your lights down to maybe 50 to 55% and gradually turn them up till you find the sweet spot. Every tank is different. Btw my phosphates are 0.37
I also run the sps ab+ schedule.

From what I understand Gen4 lights are way stronger the gen3 and I also have a diffuser on them. If I lower them to 50% brightness will it have more of a negative effect on my sps now?

What do you keep your alk and n03?

 

[Robink]

I keep my alk between 8 and 9. N03 is 20. Are you able to get a par meter? That would solve the lighting problems. If you have a local club you can probably borrow a par meter.

 

[Cyricdark]

From what I understand Gen4 lights are way stronger the gen3 and I also have a diffuser on them. If I lower them to 50% brightness will it have more of a negative effect on my sps now?

What do you keep your alk and n03?

Doesn't matter too low of light can cause corals to Brown out but they will typically recover from that and it usually takes weeks for that to even happen too much light can cause them to bleach which is what you're dealing with and that will absolutely kill them and can do it in a day it is way worse to provide too much light then it is not enough so always error on the low side.

 

[Jackooze]

Doesn't matter too low of light can cause corals to Brown out but they will typically recover from that and it usually takes weeks for that to even happen too much light can cause them to bleach which is what you're dealing with and that will absolutely kill them and can do it in a day it is way worse to provide too much light then it is not enough so always error on the low side.

So you agree with lowering to 50% and slowly acclimating back up?

 

[Cyricdark]

So you agree with lowering to 50% and slowly acclimating back up?

Yes you could maybe start 60-70% keep in mind the best thing to do would be to have a par meter, but without one of those that would be the safest option.

 

[roberthu526]

From what I understand Gen4 lights are way stronger the gen3 and I also have a diffuser on them. If I lower them to 50% brightness will it have more of a negative effect on my sps now?

What do you keep your alk and n03?

It doesn’t matter if it is G3 or G4. As long as they are both the pro version and you are set at 100% with 8” above the water, you will likely run into some issues especially when your tank is only 18” deep. Your par at the top of the waterline is likely at 700+ which can cook new frags in a matter of hours. 50% is probably a good start. And if possible I’d raise the light a bit higher too to avoid heat spot in the center.

 

[jda]

If you are going to run them at 100%, then need to be up 18-24" above the tank - there are successes with this. Also, the people who run them at 100% also run all channels at 100%.