Help with blue stag

[tankjunky]

So im fairly new to SPS, all the corals I have in the tank rite now are doing very well. except the stag, it is about 1-2" tall from about the middle to the top it has polyp extension but the bottom keeps dieing away.

Tank is standard 80 gallon
lights, 2 250 watt DE 20K
Nitrates read 0
Ph 8
Running 2 two little fishies reactors, one filled with carbon and the other has phosban in it, running for 6 days now.

Coral is about the middle of the tank directly under one Light and medium flow

 

[fcmatt]

"bottom keeps dieing away"

do you think you mean the skin of the coral is coming off near the base
and working it's way upwards?

if so that sounds like Rapid Tissue Necrosis...

how long has the coral been in your tank?

 

[tankjunky]

yes the skin is slowly coming off like you described, Its been in the tank for 3-4 weeks. It started about a week after I put it in and its very slow but its getting worse.

 

[dalston]

It's not rapid tissue necrosis, RTN would strip a coral that size overnight. Sounds like 'some tissue loss over 3-4 weeks' could be STN (slow tissue necrosis).

In any case, when asking about issues with SPS, you will need to provide your parameters of at least calcium, alk, magnesium, and specific gravity.

 

[fcmatt]

Hm. well the rapid part of Necrosis sounds incorrect then.

It is almost impossible to guess what is wrong with the coral. From being
a disease to just plain stress causing the degradation...

so a full round of water analysis is in order and thinking of anything that
could be possibly stressing out the coral like temp swings. what is your
phosphate levels? Anything bad could have gotten into the tank? etc...

 

[ingtar_shinowa]

My money is on ALK and PO4

 

[evsalty]

Alk would more likely effect the tips. I would look for red bugs or aefw's. This is on top of the params ofcorse.

 

[tankjunky]

PO4 reads 0
nitrates read 0
ph 8.1
alk is 3 meq-l
CA is around 450-500ppm. Its been around a week or 2 scinse I tested this
Mg is around 1300, Been awile for this too, but keeping high to help with an algea problem

I have about 14 other SPS corals that I can see growing or coloring up every day and this is the only one having problems. I also know I have a Po4 problem but I hooked up 2 reactors one with phosban and the other carbon and the PE on all my corals are getting a lot better

 

[fcmatt]

it could be that this coral has a disease? i was doing some reading last night from
Borneman and i have no idea which disease it could be but there are plenty from his list.

It is really hard to guess what the problem may be especially since I am very far from
being an expert or even a novice when it comes to these issues. just trying to help.

http://www.reefs.org/library/talklog/eb_jl_111598.html

 

[OneReef]

SPS can be tough anyways. I have had an SPS colony do well in my tank for 2 years, and up and STN or RTN out of nowhere for no apparent reason. Parameters need to be stable and correct for some of these delicate frags.