Please HELP!!

[morphiii]

I bought a green stylopora last Saturday at NJ reef swap.
I have a 30 gallon tank with 4*39w T5. I put the coral in the middle of the tank with pretty good water movement.
It seems to like it, the green tips are all extended and full but this morning, one of the tips is all brown and mushy looking, looks like it is covered with brown mucus.
It is still full looking just lacking the green tips. Is it dying or diseased or got attacked?
I have a 6 month old tank, is that the problem???
Please help.

 

[spanko]

Doesn't sound good, can you post a pic? These coral like moderate to high light and strong water flow.

 

[morphiii]

Here is a pic, sorry about the quality.
As I said the tip has some fleshy tissues to it, just all brown.
I added some Mg and Calcium additive yesterday.
Could it be low alkalinity? Tested it 180ppm GH and 100 KH.

 

[spanko]

The polyps look like they have died off there for some reason. Take a soft tooth brush and daily keep the area free of the brown algae you see there. If parameters are good it may grow back there over some time.

 

[gatorwpb]

do you have direct flow pointed at it? Sometimes direct flow can rip the flesh off and the brown algae will grow at that spot.
Just check to make sure it isnt getting direct flow. If thats the case and you fix it, it will grow back quickly (assuming everything else is in check).