I have a large Hawian feather duster which lost its crown a week after I got it. The week I got it, the tip of some of the feathers were getting black and then melted away. Not all of them would do that but slowly, one by one, the tip would turn black and melt all the way to the root.

Then after a week it just dropped that crown and about 10 feathers had melted already. It then spend a week in its tube without coming out and finaly last week, after a week of hiding, it came out with a tiny new crown.

Now, one week later the crown is nearly back in size to what it was, so it grew really fast and each day I can see it's growing bigger still.

But what I would like to know is what can cause the tip to turn black and the feathers to melt? Change in parameter from the LFS? Infection? blockage in the canal of the feathers?

Now the crown is beautiful and look very healthy and has not rot but I would like to avoid this crown getting the same thing as the previous one. There is plenty of food in my tank since I feed my sponge, gorgonian, scallop etc, so the feather duster is NOT starving at all. I feed Fauna Marin Ultra Seafan, Ultra Min F, roti-feast, cyclopeeze, DT live phytoplankton, Chromaplex, oyster feast, marine snow etc.. so you get the idea.

Water parameters are perfect, ammonia, nitrites and nitrates are all at 0 (yes ever nitrates). Salinity at 1.025, calcium 420, magnesium 1400, KH 8.

I acclimated it slowly over 3 hours when I first got it and strange thing is, it kept its crown out in the bag and in the transfer to the tank..so that was wierd.

So what hapened that made the tips black and melt away? what could cause this?

same thing happened with mine acutally not too long ago however mind was a little different... Dont quote me on this but IMO this kinda like a way of molting for the feather dusters mine slowly lost part and then completly came off and it was weird it came out alot with its new crown and yes it happened in less than a day or two but when the feather duster came out some with its new crown my emeralds took care of him so i no longer have one but anyways yes mine did the same thing and my para were perfect as well i think its just something they naturally do

i would say it was probably just stress,

though ive never kept the Hawaiian species my christmass tree worms will recede with even the slightest amount of variance in flow, temp, etc.

I think there is more involved than stress since the crown was rotting with black tips.

I can understand it dropping its crown from stess but I doubt stress caused the rotting. I am pretty sure it dropped the crown because it was rotting away. It did not look stressed and did not even retract in its tube during transport and acclimatation. You would think that a stressed worm would retreat in its tube, at least some time.

I don' think mine is as sensitive as yours as it does not react when I move around it to do the maintenance or when I do water change. Seem pretty much oblivious to anything going around it.

i can see how you would think that.

ive never had one of my worms rot, though they will drop individual feathers from time to time. i wish i had more experience with this specie to offer some sort of help.

Probably it's right on with stress. I had just got the worm and maybe it was just stress. I just hope it will not do the same with this new crown.