SPS bleaching issues...

I am new to SPS corals and so I don't know what to do here. I just got my first hard corals about 3 weeks ago but I noticed last night that some are beginning to go white. I assume they are dying. These are under MH lights, which are getting old. Any help would be great! My levels are the following:
Ca- 415 PPM
PH- 8.3
Ammonia- 0
Nitrite- 0
Nitrate- 15-20
KH/ALK- 9.0 dKH or 3.2 meq/L

To be honest I have a hard time trusting the Nitrates, but maybe I should...





Edited by Haley'sfish - January 01 2011 at 8:52pm

I did not really acclimate them to the lighting, they are all about mid-tank. I don't think the first is being stung, but I will move it just in case. I do not know my Mg, I do not have a test kit yet for that. I'll move them all down on the bottom hopefully that will help. Thank you SGH360, I appreciate it.

I will get my Mg tested today. What is RTN? My temp stays pretty stable at 77-78 degrees.

Right off, I don't see a problem. Can you post a full tank pic please?
RTN stands for Rapid Tissue Necrosis.
SPS really don't need any special feeding but lighting and water conditions are the most important facets of keeping them.

Do you want high flow? I'll try to get a full tank shot in the morning.

I'm guessing they are about a year old, they came with this tank so I don't know....

Im with bur01014 on this and Mark. I dont see anything wrong. its only been 3 weeks. Is there color just not as vibrant as when you saw them from where they came from? If they arent dying then I wouldnt worry about it yet. But do test Mg that is a great helper!

Some of the corals are dying, no doubt. Some are fine, and some are half dying. I'll post a pic tonight when I get home. I agree, I do need to get new bulbs. I will also go get the Mg tested again today.

Reading again through this entire thread, I have to say that it is suffering from a lack of detail.
We have yet to see a full tank pic
We don't know what level the Mg dropped to
What size of bottle of what Mg supplement
And frankly, this statement is confusing, "problem may be...dosing Mg and Alk too close to each other...." Is this saying that ALL the Mg in that bottle AND MORE has precipitated out of solution before being utilized by the coral [ unlikely]
And is it also saying that that the Alk also preciptated [again unlikely]
What level did the Alk drop to
Truth is, a Mg level of 1260 ppm isn't low enough to cause a problem anyway, by itself.
In the only pics posted, the coral look fine.
Sorry, but we cannot help solve a problem that we cannot see. There is probably something else going on in this aquarium, but how will we know?

Ok, sorry for the delay, school started this week.... It took about a week to dose about 250 g of Mg, well within the tolerances specified on the bottle. My Mg dropped from 1260 to 1170. Mark- I made the mistake of mixing my Mg and Alk in the same container (about 3 cups of water) and dripped them in my tank over the course of a day. Not smart I now know. It would have been easier to tell whether they fully precipitated if they weren't both white to begin with. It was suggested to me from a reefer to just do slightly larger water changes (approx 15%) every week and see how the parameters turn out. I think at this point that is what I am going to try to do. Is it true that some just don't make it when you transfer them? I appreciate all of your help!



Edited by Haley'sfish - January 07 2011 at 6:13pm