Acan, Trumpet and Alien Eye Dieback

[neoGeorge]

Until about a month ago, the Acans were looking fantastic and had been growing fast. But then I lost the newest Acan frag (4 months old), and the Alien Eye (3 years old) started to bleach out, then other Acans (3 years old) and a Green Trumpet (3 years old) started to die back.

The tank is 3 years old, although it has been moved twice, most recently 14 months ago.

Tank chemistry has been testing great with the Red Sea Pro kits, and an ICP from Trident on November 11, 2020 came back with pretty much everything in the green, except *slightly* low Magnesium, Potassium, Iodine, Boron, Strontium, Bromine, and Lithium. I've been dosing KZ Coral System parts 1-4 once per week, 1 ml per (recommended dosage 10 ml/week), KZ Amino Acid Concentrate LPS at 1 ml per week (1 ml per day recommended) and KZ Pohl's Coral Vitalizer at 3 drops per week (recommended 2 drops every 2 days).

My BRS 2 Part plus Tropic Marin Part C automatic dosing has been in place for over a year, getting tweaks per the Red Sea Pro tests. Tank temperature has been stable at 78 degrees, +/- 1 degree.

I recently added BRS ROX 0.8 carbon to the "sump" of the JBJ 65 gallon all-in-one.

Appreciate any suggestions on causes and remedies.

Thanks in Advance!

 

[Creggers]

I run carbon in a reactor the day preceding my 15% water change each month for around 24-48 hours. Every single month without fail I see most of my LPS (Acans especially) get uncomfortable and recede back.

I only run the carbon monthly to pull tannins out of the water and to remove any chemicals that may find their way into the system (I do everything I can to keep it clean but ya never know).

I'd never run carbon for more than a 48 hours... In my opinion, take the carbon out - I'm fairly certain it upsets corals, specifically LPS.

 

[neoGeorge]

Here's a wider tank shot (note: there is no cyano in the sand - the purple coloring was added by the camera :-)

 

[neoGeorge]

I run carbon in a reactor the day preceding my 15% water change each month for around 24-48 hours. Every single month without fail I see most of my LPS (Acans especially) get uncomfortable and recede back.

I only run the carbon monthly to pull tannins out of the water and to remove any chemicals that may find their way into the system (I do everything I can to keep it clean but ya never know).

I'd never run carbon for more than a 48 hours... In my opinion, take the carbon out - I'm fairly certain it upsets corals, specifically LPS.

Thanks @Creggers - in this case I just added the carbon this morning (in a bag, no reactor), so the receding is caused by some other factor. I also checked the nitrates using the Red Sea Pro kit and it tested out at 4, which is not a concern. I did use the High Range dilution for the test since I knew the reading would likely be in the 5 range...