Problem with Orange Montipora Digitata

[weaglereefer]

I've noticed over the past 2 weeks or so, my digitata has had recessed polyps (where as before it looked like a little orange bush/shrubery). They are still bright orange, just tucked back into the coral, so it looks like a white branch with orange polka dots. Well last night I was checking everything out before heading to bed and noticed that the polyps are extended. I checked the parameters:

Temp - 78.4 F
PH - 8.1 (I run a limewater drip at night)
CA - 460
dKH - 9.5
MG - 1200 (could this be the culprit?)
Nitrate - <5 PPM
Salinity - 1.0255

I also have a frag of purple digitata that looks the same, but purple, so it seems only the digitata is having this problem.



Daytime specs from Friday afternoon while the coral was closed up:

Temp -78.8
PH - 8.3
CA - 460
dKH - 9.0
MG - 1200
Nitrate - <5ppm
Salinity - 1.0255

The coral is placed about mid way up the tank, directly under the light fixture and in a mid-high flow area. It was doing great here for 2 months. All other SPS pieces in the tank are looking fine (blue acro placed at same height, green pocci, 2 birdsnest, tri color valida, and green mille), as are LPS and softies. I have not observed any crabs or snails climbing on the coral, nor have I seen any fish nipping at it. I just found it strange that it was open at night when it won't open during the day. I'll see if I can get a pic tonight if the lights are still on when I get home.

Oh, and when it first started closing during the day, I fragged an arm off, but the place where I fragged from has growth and orange polyps as well.

Any thoughts?

 

[weaglereefer]

I didn't think it was, but from some searching, the only thing I found similar was low MG (not that I think it's too low, but I'm going to try and get it back around 1350 or so).

 

[weaglereefer]

I'm working on that now. It was 9 on Friday afternoon, dosed a little and it's at 9.5 today, trying to work it up .25 per day or so back to 10-11. Using baking soda. 1/2 tsp mixed with RO water per day. If low alk was the case, I should be able to see some results by Friday/Saturday.

Also, why would it be that the polyps were extended at night? Limewater drip? Whatever the case, it's not dying, it's growing, but just looks weird.

 

[weaglereefer]

Cool, well I hope this works then. I'm testing with the Elos kit I purchased as part of the power buy here, so it shouldn't be that old. Maybe I'll go back to testing with my API kit...

If it works I'll feel good knowing I was on the right path anyways.

 

[weaglereefer]

Nope, bulbs are about 5 months old.

I know, you're not leading me, I was bumping the alk back up anyways.

 

[weaglereefer]

Last water change was about a week ago, about a week after I noticed something was up. I only have the API ammonia kit, but it reads 00. I just find it strange that 2 separate corals, both digitata, seem upset with the water, while other stuff is fine.

 

[jaustin]

God forbid if you lose it I got your back on restocking. That thing is taking off in my tank!

Dang Gigas clam

LOL that clam eats araganite sand for breakfast!

 

[corigan]

1200 for Mag is really not that low. I've had it down in the 800's before.. Not a good idea, but if you run it around 1200-1350 you'll be fine.

As for Elos they have dates on their test kits to check to make sure it should still be accurate.

 

[derek_s]

I would always recommend (now) to have 2 alk tesk kits. I currently use a Salifert and a API. I am always getting burned on crappy KH readings. I think the ALk kits must be really sensitive to contamination.

So I think I would get another kit, maybe API and see how close they are.

I have always had trouble with digitata, and currently have none =(

 

[derek_s]

How is the tri color validia? Mine is like a first alert system. It looks pretty good, but it is the first coral to brown out if something is off. It is better than one of those seachem ammonia alert things!

 

[weaglereefer]

Well it's definitely looking better today. More color and extension, though not fully out yet. dKH tests 14 on API and 9.5 still on Elos. My freshly mixed saltwater mixed for 24 hours at 79 degrees tests at 16 dKH on my API kit. Hadn't thought to test it with the Elos kit, but I will next time.