Brown and bleaching corals

Surfzone · Apr 19, 2018

I have an sps dom. Tank where most of my acros are browning out with little to no PE. The same with monties only some of the monties are bleaching. Recently some of the monties have regained color how ever no PE. Most of my monties are placed lower in the tank and the acros are placed all over however this seems to be happening all over the tank. I'm running an Gen 4 XR 15 Pro with diffuser at 100% using the coal lab AB+ spectrum. Flow is with 2 MP 10s on the back and 1 MP 40 on the side. Water peramiters as of last night are Alk 11, Ca 450, Mg 1340, NO3 4, PO4 0.04 all testing done with Red sea. pH swings range from 7.8 at night to 8.1 during the day. I'm using CO2 scrubber on my skimmer intake, and I'm dosing NOPOX daily. I'm a heavy feeder due to my anthias. Alk stays between 10 and 11, Ca stays between 400 and 460 and Mg stays between 1300 and 1400. NO3 & PO4 stay steady where they are and never vary more that + or -0.02 for PO4 and + or - 1.0 for NO3

cumbeje · Apr 19, 2018

I suggest ICP test.

happyhourhero · Apr 19, 2018

IMO your alk is high for nutrients that low. Perhaps slowly (slowly) let it drop down to 8ish. Would also look at backing off the carbon dosing.

J. Austin · Apr 19, 2018

Like happyhourhero said, I would recommend you lower ALK. you could also try to reduce the amount of nopox added to see if you can get some color back from increased nutrients. I know you know to take it slow with whatever you do.

Add some photos to this thread if you can.

Surfzone · Apr 19, 2018

Thanks for the insight. I'm going to try lowering alk first. Then bring up nutrients if the alk alone wasn't the issue. I'm just going to let alk fall on its own by cutting the dose by half of the daily dose and test daily [the one test that I do daily sometimes Ca too.] until the desired 8 to 9 dKH is reached. I also use red sea salt black bucket so Alk is high after mixing. I might need to switch to the the blue bucket