is this my culprit

[moosehead]

My bridsnest coral and frag are receding alot in the last couple days and I couldn't figure out why. Today I found a little white/blue starfish on my frag and when I had taken him off there was a bare white patch. Seen him yesterday as well but thought nothing of it as he was on the base of the frag and I was under the impression that they were friendly. This is my problem I have coral eating starfish, my acro and monti's are fine untouched and I lost a birdnest a couple months ago as well. Now i have figured out why...how is the best was to iradicate these guys from my tank?
All my peramiters remain very constant i dose everyday so there isn't big swings in KH or CA so my thoughs are it's must be just a pest problem.
CA 420
KH 8.1
sal 1.025
nitrates 10
temp 79.5-80

 

[markalot]

They are opportunistic and will prey on hurt or dying tissue in my experience.

Is your Alk stable?

PO4 and NO3 > 0?

Lighting correct (not too much)?

 

[basser1]

Is that an asterina starfish? If so, I have those and they have not posed any problems with my acro...

 

[moosehead]

PO4 are undetectible and my no3 is around 15ppm.
My alk is stable but i drip the addidtive into my sump and the return is close to those corals.I do it fairly slow though.Maybe i should redirect the return

 

[C.Eymann]

There are many different species of Asterina starfish, however its pretty much impossible to tell them apart, for the most part they are opportunistic feeders/ algae grazers. However, it has been documented that a few are predatory species that feed on coral. In your case the pattern of damage looks like something is munching on them, the fact you pulled one of these guys off and it left behind a dead patch, I would say thats the case

Time to look for some harlequin shrimp for sale.

Always a good reference article http://reefkeeping.com/joomla/index.php/current-issue/article/45-reefkeeping-101-

 

[moosehead]

There are many different species of Asterina starfish, however its pretty much impossible to tell them apart, for the most part they are opportunistic feeders/ algae grazers. However, it has been documented that a few are predatory species that feed on coral.

Time to look for some harlequin shrimp for sale.

Yes i agree, only problem is now to find them, I've never seen them for sale in my area.