At what temperature do SPS begin to degrade?

[-Logzor]

Over the past several month my acros have VERY slowly been RTN'ing. See the details in the following thread:

https://www.reef2reef.com/forums/general-sps-discussion/79369-acros-slow-tissue-necrosis-bacterial-4.html

That thread is kind of outdated now that I think the cause is temp related, not bacterial. Now I want to explore what low temperatures do to acros and other sps.

My aquacontroller jr. probe was reading incorrectly, by at least 4 degrees. So my tank was running between 71.0-72.5.

At what point do acros begin to die / RTN. I'm sure they can handle low temps for a week or so, but what happens over months?

Has anyone else had experience with acros at sustained low temperatures? Please keep this geared towards low temperature, as in my case I'm not concerned about what happens in the high-end range.

 

[Otter_rs]

I've never kept an aquarium that low for that long. Would make sense that acopora sp. would react negatively to that low a temp. for that long. Please let us know what you learn, I'm rather interested. I would take this opportunity to do an observation journal while you slowly increase the temp.

 

[-Logzor]

Basically what has been happening over the past several months is, my acros would slowly RTN. Maybe 1-2 mm a week. Very slowly to say the least.

Eventually, the RTN would consume the entire coral.

Most LPS look fine. Some montipora look great, but most are far more pale than they should be.

Zoas are doing fine.

I'll report my findings over the coming weeks. I expect the recovery to be slow.

 

[Fieroguy19]

I am not surprised that you were having problems if your temp was that low. I doubt you will find very many people that have ran their tank that low, especially an SPS tank. Most aquarium controllers have problems with temp probes from time to time, that is why I switched to a ranco controller for temp. I have never heard of one breaking. I also keep a $2 thermometer in the sump.

 

[-Logzor]

I am not surprised that you were having problems if your temp was that low. I doubt you will find very many people that have ran their tank that low, especially an SPS tank. Most aquarium controllers have problems with temp probes from time to time, that is why I switched to a ranco controller for temp. I have never heard of one breaking. I also keep a $2 thermometer in the sump.

Yeah I'm hoping to find another case to confirm similar problems.

I'm actually surprised things didn't do worse considering how low the temperature was. If it were not for my beer brewing hobby I don't know how long it would have been before I caught this...