Pincushion Urchin "Blue Tuxedo"

[KarenH]

I ordered online and received a "Blue Tuxedo" Urchin. I acclimated him properly, but notice that he is losing some of his needles. He really hasn't moved in my tank, but I can see that his needles underneath are moving somewhat, so he's definitely alive.

This is my first Urchin and I'm hoping some knowledgeable person can give me advice on if this needle loss is just stress or something more. I would also greatly appreciate any advice on how to make this beautiful little guy happy.

[zhenya]

Hi Karen,

I ordered online and received a "Blue Tuxedo" Urchin. I acclimated him properly, but notice that he is losing some of his needles. He really hasn't moved in my tank, but I can see that his needles underneath are moving somewhat, so he's definitely alive.

I'm not an expert on Echinoderms, to put it mildly, but I think what you describe is definately reaction to stress. Most of the time it is salinity that give echinoderms such hard time when they are introduced to aquariums. At least in my experience it was the most common problem.
They require full strength salinity of 35ppt or 1.025-1.026 sp.gravity.

PS. Here's an exellent article about sea urchins, if you haven't read it already.
Sea Urchins, A Tasty Subject

[kevinpo]

Hello and welcome to Reefland!

Usually the Royal or Tuxedo urchin does not recover when it begins to lose its spines It is a sign of stress which is often caused by changes in SPG. They can be kept in SPG ranging from 1.023 - 1.026 but they can't take sudden changes in SPG. .002 is maximum. Many of the wholesale suppliers run their SPG at 1.019 - 1.021 which can be too low for urchins and some starfish. They usually die in 7-14 days. If they last longer than that they are usually good. A sign that the Tuxedo is doing well is they will collect pieces of algae, shells, and small rocks on their back and carry it around. I even had one that picked up a colony of Xenia which it carried for months. They eat many types of macro and micro algae. They are also much less prone to pushing/knocking rock and corals around compared to other urchins. I acclimate then for about 3 hours before introducing them to the tank.

I wish you luck with yours!

HTH,
Kevin

[KarenH]

Thank you so much for the info and the valuable link. There's nothing more sad than to watch one of your little sea friends slowly die and that's what happened. Our water parameters checked out perfect, but I think my mistake was in not checking the water parameters in the bag the Urchin came in first to see what he was accustomed to living in.

[Sleepy Clownfish]

Invertebrates, although people consider them fragile are actually very hardy. Acclimating an urchin correctly is key. Acclimate the urchin no less than 15 minutes using a fast drip method (1 - 2 drops per second) and no longer than 30 minutes. They'll adjust to the salinity change during this time, as will most invertebrates from my personal experience. I have used this technique with all of my invertebrates and have yet to lose one due to poor parenting.

When an urchin loses its spines it typically is a sign of stress. This isn't always a life threatening issue, although it is a sign of significant stress. Allow it some time and try not to pester it often for the next few days.

[kronos5]

mine is doing fine, he does like to collect objects and put them all over him. salinity does need to high