Corals turning white and dying

[sethd78]

I’ve had these corals for 3 plus years and as far as I know I haven’t changed anything. My water parameters all seems decent. Nitrates at 5
Phosphates are 0.16
But just recently all 3 of my 5 SPS have started turning white at the base and it’s slowly spreading out towards the tips. As they are turning white brown algae is growing on them.
coincidentally, my leather coral won’t open and extend polyps and my bubble coral has regressed. All my other lps and soft corals are fine and my lettuce coral, birdsnest, and acro are fine. So confusing.

 

[thereefhotspot]

I’ve had these corals for 3 plus years and as far as I know I haven’t changed anything. My water parameters all seems decent. Nitrates at 5
Phosphates are 0.16
But just recently all 3 of my 5 SPS have started turning white at the base and it’s slowly spreading out towards the tips. As they are turning white brown algae is growing on them.
coincidentally, my leather coral won’t open and extend polyps and my bubble coral has regressed. All my other lps and soft corals are fine and my lettuce coral, birdsnest, and acro are fine. So confusing.

I would say that the best bet is to get an ICP analysis done if your parameters are where they normally are. Unfortunately, sometimes there are things that we can't catch on our own.

- Gavin

 

[Reefer/0]

The leather coral might be going into shed and releasing toxins- and Sps are more sensitive to it? Never experienced this myself but the general advice is to run carbon to absorb some of these toxins

 

[ScottB]

I will second the ICP. Just helps narrow things down a bit. Nutrients look fine.

I would also review the basics:
- double check refractometer calibration with a second
- double check all pumps and wet MAGNETS
- test kit expirations
- RODI cartridge age, membrane. Municipal water supplies very in quality by season.

Much less likely, but STN from the base can be a sign of red bugs or white bugs (tegastes). I was having a similar issue and went for the Interceptor treatment which SEEMED to resolve the issue. Consider as a last resort, as there are some downsides. That said, many/most professional acropora growers dose the stuff prophylactically.