green star polyps dying? being eaten?

[notyelo]

I have had a group of green star polyps for about a year now. They grew in numbers and even propagated over to next live rock. Last month I noticed a decline in health. Checked all water levels and all good. I do once month 15% water changes. Tank is 160 gal. Other corals doing fine. The star Polyps are pulling away from the rock to which they are grown to, sort of flaking away and no longer coming out and flowing with the current sort of only about 1/8 in showing where as before they shown about 1/2 inch on the denticles. Beautiful flowing green. The only thing I can find different is a slim-like material that is connected from the rock on which they are growing to the rock to which is next to it. This appears to be a slim- debre coated tunnel of some sort. I can remove it and it is back the next day. Any takers on this question?

 

[steve-s]

Please post some info about your water quality numbers as well as what the nearest coral to the GSP is. What species of urchin do you have and does the coral look like it's simpley receding or the victim of predation?

Can you post a pic of the coral up close and one of the general area?

Cheers
Steve

 

[Terrier]

Notyelo, did you ever get an answer to your question? I had the same thing happen to me. My green star polyps were doing great... expanding all over my live rock to the point where I was worried that it was taking over and I'd have to remove some of it. Then suddenly it started dying, flaking off like you said. Nothing else in my tank - corals, fish, inverts, became sick. I couldn't tell if it was some sort of predation or not. My hermits were definitely picking at it, but I'm not convinced they killed it, but rather were being opportunistic when the coral was weakened by something else. My water quality was perfect (confirmed by the local store) although my alkalinity was low, but not low enough to cause dye-off. They couldn't explain it either, although they thought maybe it was a bacteria specific to that species of coral.

That was months ago, and ironically enough a few of the individual polyps hung on and it appears to be making a comeback!

To anyone else who may read this, are there any worms or other nocturnal hitchhikers that may choose to feed on this type of coral, but stays hidden so I'm not aware I have it? I have seen a few strange fuzzy worms late at night, but not long enough to make a good ID.

THanks!

 

[Terrier]

Oh yeah, the adjacent corals near my GSP include birdsnest and pulsing xenia. But my GSP died off everywhere in my tank, even in places in the middle of rock not adjacent to other corals, so I don't think coral competition did it in.

 

[melosu58]

I dont know about your tank but the other person only did a 15% PWC once a month. This is not enough to take care of reducing nitrates and replenishing trace elements. A tank can only take this but so long and then CRASH. JMO. I know he said that other corals were OK but some are more suseptable then other corals IMO.