Corals bleaching!

[orion]

Help please!

Over the last two days I noticed these two corals bleaching. I’ve had them for almost 10 years but have not seen this happen before.

So far all other corals, clams, and fish are fine. No signs of stress or bleaching on my LPS corals.

<img src="http://www.photodump.org/stored11/Bleach1.jpg">
I first noticed a small part bleaching two days ago; it has progressed into this today.

<img src="http://www.photodump.org/stored11/Bleach2.jpg">
This happened today; I noticed it loosing some color yesterday but was white when I got home today.

<img src="http://www.photodump.org/stored11/Bleach3.jpg">
Two polyps on the right fell off yesterday as well as one in the lower left. One in the center left is dieing today.

PH: 8.35
Calcium: 420
DKH: 8.5
Phosphates: 0
Nitrates: 0
Nitrites: 0

Recent changes:
A few weeks ago I added emerald green crabs and more snails. I’ve been dealing with cryo and other green algae’s which I noticed were dieing off rapidly over the past week. The only chemical change I made in the last two weeks was adding prestone driveway heat as a calcium supplement. I’ve only dosed it twice and was about 6 teaspoons each time. I normally dose b-ionic at night. I also changed my phosban and carbon last weekend.

If anyone can offer me some suggestions I’d really appreciate it.
Thanks,
John

 

[DrBDC]

How are you dosing the prestone? Are you mixing it in water first and then adding it as a solution? Where are you adding it to? Main tank or sump. Also, was yoiur dKh reading before or after dosing?

 

[orion]

Thanks for the response. I'm mixing the preston w/600ml of water and dripping into my sump with a drip bag. I've only dosed it twice over the past two weeks and did it very slowly( 3 hours). DKH has been steady between 8-9. Last time I added prestone was 3 or 4 days ago.

 

[DrBDC]

Have you seen the emeralds anywhere around those polyps or sitting on/near the first pic coral.

 

[orion]

One of the emeralds has been spotted sleeping in the first coral but there is no bleaching in the area he was seen, he was on the other side of it. I have not seen him pic at anything besides algae.

 

[orion]

Something else I thought of; I’ve been adding Seachem Iodine over the past two months. I use 1 capful per week. My coral banded shrimp lost an arm/claw after a molt which prompted me to start adding iodine. His arm grew back but lost his other arm two molts after that.

I did a 10 gallon water change last night to see if that helps.

This morning I could see what looked like one of the polyps falling out of the coral in the first picture intact, it was on the edge of the bleached area.

Would it help to frag the first coral or cut out the bleached area?
Thanks again,
John

 

[DrBDC]

Are you testing for iodide levels? If not, stop adding it. That will remove a variable. What kind of coral is that first pic? From the close up it looks like a cross between a softy and a monti cap.

 

[JxMetal]

pagoda cup?

 

[orion]

I have stopped adding iodine and do not have a test kit for it. From searching on reefcentral I got the impression that there was not a good iodine test kit. Some suggest adding iodine and others do not. I believe it is a pagoda cup. The odd thing is the problem is only affecting my stony corals. My LPS show no signs of stress or bleaching. Thanks again for the responses.

 

[orion]

I fragged the plate coral / cut off the dying part, hopefully it will help. The Pagoda cup lost more polyps in the center. I'm wondering if I should remove it from the tank. If anyone has suggestions I'd appreciate it.
Thanks,
John

 

[Nanook]

Do these corals get any direct flow from a powerhead or other irritant? The small polyp stony coral looks like it is going into Slow Tissue Necrosis or STN. The pagoda cup, not sure. I would be inclined to think it is being eaten or irritated by something...perhaps the crab. Can you remove the crabs to see if that helps?

The STN could be secondary to a rise in alkalinity dt dosing. But, if this has been your routine using the prestone stuff for a while, then it might not be that. I would be suspicious of that as the culprit for a spike though. I wouldn't frag either coral or remove them from the tank....I think I would just watch them both and stop adding the prestone, perhaps take the crabs out and see what happens. Once STN sets in, the coral usually dies in my experience...but not sure what others have seen.

 

[Nanook]

Any changes in bulbs or temperatures...any temp spikes?

 

[capncapo]

Adding iodine will cause your shrimp to molt prematurely. Continued premature molting will eventually kill it.

 

[orion]

I did lower my temp controller 1 degree in the last week. It use to fluctuate between 79-81, since the change it has been between 78-80. I changed it back today. Do you think that could cause the problem?
I will discontinue using iodine.
Thanks!

 

[capncapo]

<a href=showthread.php?s=&postid=9388324#post9388324 target=_blank>Originally posted</a> by orion
I did lower my temp controller 1 degree in the last week. It use to fluctuate between 79-81, since the change it has been between 78-80. I changed it back today. Do you think that could cause the problem?
I will discontinue using iodine.
Thanks!

NOPE!

 

[Lost His Marbles Name]

Is there any pumps of metal rusting in your tank? I have had a crash due to rust. I was More tham mad.

 

[orion]

No rust that I know of but will check all pumps.
Thanks!