Crinoid behaviour question

[sixty_reefer]

@Jay Hemdal @Thales I wonder if you guys could help me in any way on this question.

Recently I’ve acquired a crinoid feather star and I’ve been feeding it a variety of unicellular zooplankton, the feeding seems to be working and fecal excrement are observed daily.

My question is more regarding behaviour.
I’ve noticed that every now and then the crinoid will drop a partial part of the feather, this started a few days after introducing it to the new tank. Will this be a stress reaction to the new environment or is it trying to rebuild parts of the body that could of have been damaged previously due to finding itself with a constant supply of food?

I’ve also noticed that some of the first feathers that he lost are being regrown inclusive the cirri

Im looking for opinions on how to proceed from here, should I look at getting a larger tank in order to reduce stress and reduce water chemistry impact, should I reduce feeding (can a crinoid be over fed?), look for a possible parasite or do nothing for the time being and continue observing.

I’ve also noticed that string sounds do create a a impact on the start could sound be a issue in keeping this in home aquaria?

 

[LovinlifeinGuam]

I dont believe that dropping pinnules is ever a good sign.

 

[Jay Hemdal Verified Community Expert]

@Jay Hemdal @Thales I wonder if you guys could help me in any way on this question.

Recently I’ve acquired a crinoid feather star and I’ve been feeding it a variety of unicellular zooplankton, the feeding seems to be working and fecal excrement are observed daily.

My question is more regarding behaviour.
I’ve noticed that every now and then the crinoid will drop a partial part of the feather, this started a few days after introducing it to the new tank. Will this be a stress reaction to the new environment or is it trying to rebuild parts of the body that could of have been damaged previously due to finding itself with a constant supply of food?

I’ve also noticed that some of the first feathers that he lost are being regrown inclusive the cirri

Im looking for opinions on how to proceed from here, should I look at getting a larger tank in order to reduce stress and reduce water chemistry impact, should I reduce feeding (can a crinoid be over fed?), look for a possible parasite or do nothing for the time being and continue observing.

I’ve also noticed that string sounds do create a a impact on the start could sound be a issue in keeping this in home aquaria?

Sorry - I stopped trying to keep these many years ago. Non-living foods just don't seem to work, and live zooplankton wasn't a cost effective option for us. We have done better with basket stars.

Since you are feeding live foods and have seen some regrowth of the lost pinnules, maybe you'll fair better. Here is a link to an article about their care, but note that the author doesn't really document much in terms the of the longevity they saw:

https://reefs.com/magazine/a-journey-in-crinoid-keeping/

 

[sixty_reefer]

I dont believe that dropping pinnules is ever a good sign.

I agree, research shows that can be loads of different factors, trying to figure seems to be impossible. Hence asking for the opinion of a extra pair of eyes.

 

[sixty_reefer]

Sorry - I stopped trying to keep these many years ago. Non-living foods just don't seem to work, and live zooplankton wasn't a cost effective option for us. We have done better with basket stars.

Since you are feeding live foods and have seen some regrowth of the lost pinnules, maybe you'll fair better. Here is a link to an article about their care, but note that the author doesn't really document much in terms the of the longevity they saw:

https://reefs.com/magazine/a-journey-in-crinoid-keeping/

Thank you, I’ve read this one recently and it seems very vague in terms of behaviour, I’ve read on another thread that someone lost all of his after two years to a nitrate spike.
I always thought that as long as feeding was enough that care shouldn’t be a problem, it seems that I was very wrong on that assumption.
What size thanks did you used to have them in?

 

[Jay Hemdal Verified Community Expert]

Thank you, I’ve read this one recently and it seems very vague in terms of behaviour, I’ve read on another thread that someone lost all of his after two years to a nitrate spike.
I always thought that as long as feeding was enough that care shouldn’t be a problem, it seems that I was very wrong on that assumption.
What size thanks did you used to have them in?

I’ve tried them in established reefs from 40 to 2000 gallons.

I forgot to mention - you said you are seeing feces. There is a phenomenon that I ran into when trying to raise zebra mussels; I was feeding them phytoplankton, and is was seeing “feces” and I thought things were going well, but the mussels all starved. Turns out what I was seeing were “Psuedo feces”, essentially, undigested plankton that the mussels were filtering, but not actually digesting because it wasn’t “appropriate”. If you have a microscope, look at some of these feces to ensure the material was digested and not just mixed with mucus and expelled.

 

[sixty_reefer]

I’ve tried them in established reefs from 40 to 2000 gallons.

I forgot to mention - you said you are seeing feces. There is a phenomenon that I ran into when trying to raise zebra mussels; I was feeding them phytoplankton, and is was seeing “feces” and I thought things were going well, but the mussels all starved. Turns out what I was seeing were “Psuedo feces”, essentially, undigested plankton that the mussels were filtering, but not actually digesting because it wasn’t “appropriate”. If you have a microscope, look at some of these feces to ensure the material was digested and not just mixed with mucus and expelled.

Above is one image at 40x from what I thought to be feces, I’ve seen some baby bristle worms eating it. So you may be right in saying that it may not be fully digested.
I still don’t know what that big thing in the centre is.

 

[Jay Hemdal Verified Community Expert]

Above is one image at 40x from what I thought to be feces, I’ve seen some baby bristle worms eating it. So you may be right in saying that it may not be fully digested.
I still don’t know what that big thing in the centre is.

That's tough to say - it is probably normal for them to excrete bits of shell from copepods, etc. Can you recognize any whole food items in the feces? In my case, I could see undigested, still green algae cells in the pseudo feces.

It made me chuckle - Wikipedia actually has a page devoted to this topic:
https://en.wikipedia.org/wiki/Pseudofeces

 

[sixty_reefer]

Y

That's tough to say - it is probably normal for them to excrete bits of shell from copepods, etc. Can you recognize any whole food items in the feces? In my case, I could see undigested, still green algae cells in the pseudo feces.

It made me chuckle - Wikipedia actually has a page devoted to this topic:
https://en.wikipedia.org/wiki/Pseudofeces

Yes, most of the expelled content it’s organic carbon, I’ve been using this to propagate Protozoa in the system.
The colourless organic carbon particle tends to form a “floc” wile in the tank full of bacteria and Protozoa.
I’ve observed that in the fences the same carbon is present in a orange colour but no signs of bacteria or Protozoa.
My intuition says that enzymes in the crinoid stomach are reacting with the carbohydrate and causing a colour change.
As I can’t see Protozoa in fever I would believe that they would be fully digested.

I’ve also believed I’ve identified the answer to my earlier question yesterday wile dosing silica in order to try and increase some natural phytoplankton.