20g high w/ xr15. Sps dying on the shadow side.

[a.t.t.r]

Having some issues in my 20 gallon. Have a xr15 with diffuser mounted 8 inches above water with the led buttons faceing front and I am getting lots of issues with self shading I think. Corals are dying on side that is in shadow.
I have looked into the option of the reefbrite chi but don’t think 10 inch light bar is really gonna do much.

I am considering a second xr15 mounting them both so the wider portion of the led goes front to back (power buttons facing to the sides of tank) and mounting them at a slight inward facing angle.

any thoughts? I am new to led but never had this issue in the past with point source lights like halides even mounted in tiny reflectors.

 

[Tonycass12]

Whats your light settings like?

 

[a.t.t.r]

Whats your light settings like?

12 hours (mostly blue) 7 of those hours above 40 percent(some white) 5 of those above 60 (more white)and comes to a peak at 80 percent (single point all maxed) before going back down. I thought sps shared nutrients with the polyps in the shadow.

 

[Tonycass12]

12 hours (mostly blue) 7 of those hours above 40 percent(some white) 5 of those above 60 (more white)and comes to a peak at 80 percent (single point all maxed) before going back down. I thought sps shared nutrients with the polyps in the shadow.

Yes and no. I still get die off on the completly shaded portions of sps but its not bad by any means. I would recommend renting a par meter, knowing how much light your actually getting at different set points will help you factor out a couple things right off the bat. i was really surprised with the numbers I was getting off one xr15 over my tank so I did add a second but my display is almost 2x the size of yours. Ive slowly been cranking them up I run mine at about 80% and I'm looking to eventually run my 2 fixtures at 90-95% with all the channels at 100% for 4-6hrs a day before scaling back to something more like ab+ for an additional 2-3hrs(i will only change the schedule by 15minutes a month to extend that high intensity and I dial up each color only 5% a month at most to try and avoid stressing the corals). Here is my current schedule and some par readings from 2 fixtures over my 24x24x16tall tank. With just one xr15 I would have been skeptical about how acros would do in anything but the very top of the tank now im comfortable placing them almost anywhere ive got some high end acros and tabling acros up top with birdnest, stylos and montis from the sand to about half way up the rocks. Hope this all helps!


The par numbers I have listed were when I was running just an ab+ schedule the point intensity was set to 100% with the schedule intensity set at 95%. Im planning on renting the par meter again from my LFS to get clued in on more of where I'm at now when my schedule peaks but if I had to guess top of the rocks are 400+par with the sand around high 200s-300

 

[a.t.t.r]

I have a par meter an old one from the MH days so it can be a lil off when it comes to heavy blues but the numbers are all good (when aiming up) Anyways I went out and bought a second xr15 figure I’ll upgrade someday anyways. I have a 65g fw but I love the 3 remaining fish in it so it’s staying fw for a long time.