What happened to my German Blue Montipora Digitata?

[MrX]

At last months meeting I bought a German Blue Montipora Digitata from Eric (eaze333) and it appeared to be doing fine (along with my other SPS). Last night I looked into the tank and the coral looked like it had been sandblasted!?! Any ideas what could have happened?

Here's a pic from Eric's original sale thread. You can see where I drew some white lines over it. Those parts were basically wiped out. I'm guessing all that I see now is the skeleton.

Placement was about 3/4ths of the way up in the tank, in the middle of the tank, almost level with powerheads. LEDs only come up to 35% blue/40% white.

The only thing that has changed recently is that I changed my Apex from alternating the two powerheads every 15 minutes, to alternating every 6 hours.

See my sig for my livestock list. Would/could a halloween urchin have done this?

The Pink Birds Nest I bought at the same time appears to be doing really well; lots of white tips and even a new branch or two forming.

How else can I judge the health of SPS? If I look with a magnifying glass should I see lots of polyps/etc.? Night, day, or both?

Thanks!

 

[dannyp02908]

what are your parameters? That is needed info for anyone to try to troubleshoot the issue.

As for polyp extension, i can see the polyps on all my SPS clearly with no magnifying glass. i have a cap, unknown monti, couple digis, stylo, cpl birdsnests and green slimer.

 

[Turbosnail]

+1 a list of your parameters would help. It sounds like RTN(rapid tissue necrosis).

 

[MrX]

Sorry, duh. Here's my last test from the 17th:

pH: 8.2
Ammonia: 0
Nitrites: 0
Nitrates: 0
Calcium: 460
Carbonate Hardness / Alkalinity: 7.2dKH / 2.6meq/L
Magnesium: 1350-1380

Prior to that on 05/02/2012 I got:

pH: 8.2
Ammonia: 0
Nitrites: 0
Nitrates: 0
Calcium: 440-460
Carbonate Hardness / Alkalinity: 8.2-9.0 / 2.96-3.18
Magnesium: 1410-1440

Don't read too much into the differences between ALK/MAG tests on those two days. I've only done the test twice and the first time I don't think I was going slow enough.

To me it looks like a trail from the urchin eating stuff.

Forgot to mention in the first post... I was trying to find a new spot for it and to do so I had to take it off the frag plug. It came off easy enough but butter fingers me dropped it, it hit the floor, and shattered like a china plate. I had one little 'tree' piece left which I stick in a hole in the rocks. A couple other smaller pieces I just stuck in random places. I don't really expect much if anything to happen with them.

 

[frank180reef]

HI
your alk is a bit low, that is likely the cause

 

[eaze333]

alkalinity is a little low. an alk swing wouldn't necessarily affect everything in the tank, but some corals just don't like it. Judging by your stock list I would assume you are not dosing anything yet, but I would get in the habit of testing your alkalinity a little more frequently because lack of stability in alkalinity can be a real B...especially when it comes to corals magically RTN'n. LPS will shred due to alk swings also, especially chalices. It will give you a good idea of your what your tank is consuming, and when you might need to begin dosing. A little preventive maintenance. At this point I would think regular water changes should keep up with you current tank demands. For the pieces you still have left, if you can get them glued to a piece of rock they should grow pretty fast. depending how far the "tree" piece is in the hole,that part out of light and flow might die on you. German blue is definitely one of the hardiest and fastest growers for me, . If you would like me to set you up with another piece shoot me a pm. I got plenty, that's no problem. You can even stop by the house if you like, LMK. As far a polyps, my mommy has it's out 24/7, very pretty
Large Image Link (323 kB)

 

[MrX]

No, not dosing anything yet. Once I get my PM1 set up and the ATO going I'll start researching dosing.

Most of the little pieces have disappeared. The one larger piece is stuck into a hole in a rock to see what happens. My other SPS still have polyps that I can see without a magnifying glass, but there isn't a lot by any means on any of them.

I'd do a water change tonight and see if that helps anything.

Eric - I'll PM you about stopping by sometime, etc.

Thanks!

 

[Matt W]

Question about this discussion on dosing, in this case your alk needs to be adjusted into specification near 8-10 and then you begin dosing. Is this correct? If so, then you would adjust alk up with NaHCO3; then begin a dosing regiment?

 

[SteveDola]

HI
your alk is a bit low, that is likely the cause

its not about the number as long as its within an acceptable range. the most important part is stability. I have my tank at 7.5 alk and its rock solid with no sps problems. Many people run their tanks at the low end...as long as its stable, its find. I think his bigger problem here is that its fluxuating from 7.2 - 9. You need to test regularly with good kits and dose a measured amount of 2part according to the demand of calcium uptake in your tank.

 

[MrX]

its not about the number as long as its within an acceptable range. the most important part is stability. I have my tank at 7.5 alk and its rock solid with no sps problems. Many people run their tanks at the low end...as long as its stable, its find. I think his bigger problem here is that its fluxuating from 7.2 - 9. You need to test regularly with good kits and dose a measured amount of 2part according to the demand of calcium uptake in your tank.

I'll look into two part dosing after I get my ATO stuff done and my wallet can breathe a little. In regards to the two earlier ALK tests, they were probably much closer than the numbers I posted. That was my first and second time testing and I'm sure I didn't go slow enough so thus the skewed readings. As I do it more I'll become used to it and be more confident in the numbers. I have API for the basic stuff and CAL, and Salifert for the ALK/MAG tests right now.

 

[frank180reef]

Question about this discussion on dosing, in this case your alk needs to be adjusted into specification near 8-10 and then you begin dosing. Is this correct? If so, then you would adjust alk up with NaHCO3; then begin a dosing regiment?

you can dose sodium bicarbonate to raise the alkalinity also...................as well as to maintain it.

it has been a while since I took chemistry so is that what NaHCO3 is?

 

[SteveDola]

When I do testing and I think I was incorrect in my attempt I start from scratch. ALong with my visual interpretation, these tests are the bench mark for which I determine how the tank is going. If my tank tests alk at 7 and it had been at 9 a week prior, I know that corals are uptaking more than I am dosing and have to adjust (just an example). If I accept an inaccurate reading then what ever plan of recovery I have to achieve my desired results is going to be inaccurate.

SPS corals (even digitatas, prolly the easiest of the group) are not as easy as zoas, toadstools, and lps. They require consistant water chemistry, low NO3+PO4, good flow/good lighting. When their requirements are not met then poor color, STN/RTN, no growth, and/or death occur. 2 part supplements are actually not too expensive and can be obtained at any lfs...the bigger the jugs the better deal. Test kits can be expensive but most LFS I know will test your water if you take them a sample. If you plan on keeping SPS then I suggest that you try to meet their requirements to achieve happy corals.

 

[Matt W]

you can dose sodium bicarbonate to raise the alkalinity also...................as well as to maintain it.

it has been a while since I took chemistry so is that what NaHCO3 is?

Sorry, yes it is bicarb.

My question is MrX pH is acceptable but alk is low and/or fluctuating. Therefore, is it preferred to adjust Alk into specification with NaHCO3 which will not raise pH as much as CaOH (kalk); then begin a dosing regiment such as two-part or kalk?

 

[JohnK]

Yes, correct the alk then figure out the dosing plan. If you try to raise alk with alk or two part you will be raising Ca at the same time. The correct approach would be to use baking soda, the alk part of 2 part, or another alk specific additive to bring the alk to where it should be, then work out a daily dosing routine with 2 part and or kalk to maintain both Ca and alk in balance.