What would cause 1 single Acro to STN but not any others?

[Reef Puncher]

So if there was a salinity or alk crash or spike, wouldnt it affect more than just one single acro? All of my other acros, goniopora, and sensitive corals are doing fine. But one of my acros just decided to slowly start dying. i think i might try fragging the one spike not affected. the base is all but gone. But what would cause 1?
The only thing that swings in my tank is phosphates. everything else is pretty stable. after a year in the hobby, to this day i cant get stable phosphates. it ranges anywhere from 0 to 0.1. most often it sits around 0.06. if swinging phosphates were that bad, wouldnt it affect more than one acro? anyone know possible causes?

 

[Formulator]

I don’t think phosphates are the issue. I would not call +/- 0.05 ppm a “swing” by any stretch of the imagination… You are in a good spot there. Not all acros are the same and some will tolerate conditions better than others. This is especially true of light, with some species doing much better than others in lower PAR. Dying from the base up could point to light as a potential culprit. Have you measured PAR in your tank?

Also, acros in general are finicky and your story is not uncommon. Sometimes they just die and there is not always an obvious reason, and other corals seem just fine. It is the bane of many reefers.

 

[exnisstech]

Following because I have no idea why one piece will STN or RTN when everything else is fine. I just accept it but would love to hear a reason why if someone knows.

 

[Reef Puncher]

I don’t think phosphates are the issue. I would not call +/- 0.05 ppm a “swing” by any stretch of the imagination… You are in a good spot there. Not all acros are the same and some will tolerate conditions better than others. This is especially true of light, with some species doing much better than others in lower PAR. Dying from the base up could point to light as a potential culprit. Have you measured PAR in your tank?

Also, acros in general are finicky and your story is not uncommon. Sometimes they just die and there is not always an obvious reason, and other corals seem just fine. It is the bane of many reefers.

yea its around 340 par on my top rock shelfs. hmmm. it is worth noting that i glued it kinda sideways, so that the stalks were not straight up, because someone told me it grows faster that way. but the stalks shaded one side of the base. and thats where the STN started, in the shade of the stalk...... but i didnt think a slight small spot of shade when the rest of the acro is getting 340 par, would be a problem you can see in the image its only a small small line of shade? i wonder if thats correlated? see my image below

 

[Formulator]

Hmm, that should be sufficient light. Maybe look for bugs or another predator. Any questionably reef safe fish (angels, file fish, etc)? Also, not sure if I’m looking at the right thing, but that orange coral near your arrow point looks more like a pectina than acro to me. I also don’t really see any corals in there that I would call “sensitive”, for comparison to an acro. What are all of your other parameters?

 

[Reef Puncher]

Hmm, that should be sufficient light. Maybe look for bugs or another predator. Any questionably reef safe fish (angels, file fish, etc)? Also, not sure if I’m looking at the right thing, but that orange coral near your arrow point looks more like a pectina than acro to me. I also don’t really see any corals in there that I would call “sensitive”, for comparison to an acro. What are all of your other parameters?

this is just one part of my tank. i have other acros, goni's, torches, all sorts of corals. its def a acro, its PC rainbow acro, its just a wierd pic.

Alk- 8.5
Calc- 420
Mag- 1390 (working on getting it a little higher)
Nitrates- 10
Phos, ranges as i mentioned.
Salinity-1.026 tested using a hand held refractomter, and milwaukee digital refractometer


god parasites would be the worst, i hope not. what about bacteria infection?

 

[Formulator]

this is just one part of my tank. i have other acros, goni's, torches, all sorts of corals. its def a acro, its PC rainbow acro, its just a wierd pic.

Alk- 8.5
Calc- 420
Mag- 1390 (working on getting it a little higher)
Nitrates- 10
Phos, ranges as i mentioned.
Salinity-1.026 tested using a hand held refractomter, and milwaukee digital refractometer


god parasites would be the worst, i hope not. what about bacteria infection?

Ah ok. I see the rainbow now. I was looking at the orange one behind it, which is a beautiful piece BTW. What is that one? I could use some orange in my tank.

Your parameters look spot on to me. Light sounds appropriate. That just leaves flow and other causes like predators. Based on the healthy appearance of the other stuff, I doubt flow is an issue. I would get out a flashlight an hour or 2 after dark and see if you can see any culprits. Hopefully that is not it, but better to find out now and get a plan of action before it affects other corals. I suppose bacteria is possible, but that’s much more common in LPS and softies.

 

[Formulator]

Following because I have no idea why one piece will STN or RTN when everything else is fine. I just accept it but would love to hear a reason why if someone knows.

I think it is one of the great mysteries of our hobby… often there isn’t a definitive answer, unfortunately

 

[Reef Puncher]

Ah ok. I see the rainbow now. I was looking at the orange one behind it, which is a beautiful piece BTW. What is that one? I could use some orange in my tank.

Your parameters look spot on to me. Light sounds appropriate. That just leaves flow and other causes like predators. Based on the healthy appearance of the other stuff, I doubt flow is an issue. I would get out a flashlight an hour or 2 after dark and see if you can see any culprits. Hopefully that is not it, but better to find out now and get a plan of action before it affects other corals. I suppose bacteria is possible, but that’s much more common in LPS and softies.

its an orange montipora setosa. yea i will get out a flashlight and look later. actually i might frag it to try to save it.
my flow is solid two mp10s and a small wavemaker in the back. im so anal about getting my flow just right haha. torches need to lightly sway but acros need more flow, so i spent weeks tweaking it.