URGENT! Sea Urchin Question
- Thread starter samwrang
- Start date
ACBlinky
Premium Member
Dropping spines is often a sign of a doomed urchin, but not always.
Things to look into:
1. Check ALL your water parameters, make sure everything is as perfect as can be. Urchins are sensitive critters and don't respond well to high nitrates, low Ca & alk, low salinity or anything that varies widely from natural seawater parameters.
2. Is the urchin getting enough to eat? Is there coralline on the glass/rockwork for him to graze?
3. Is anything - fish, crab, shrimp - picking on the urchin? If something was off and you correct it, he won't be able to recover if he's being harassed.
Do try and see what you can do. My urchin started dropping spines a few months back - I had no idea, but there had been an ATO mishap and the SG had dropped from its usual 1.025 down to 1.021 and Speedy nearly died after a few days in these conditions. I corrected the problem as soon as I found out, made sure he had food to eat and wasn't being picked on, and over a matter of weeks he slowly healed. There were days I was certain he had died - once he lay upside down on the sand for hours - but he made it through. Best of luck.
Things to look into:
1. Check ALL your water parameters, make sure everything is as perfect as can be. Urchins are sensitive critters and don't respond well to high nitrates, low Ca & alk, low salinity or anything that varies widely from natural seawater parameters.
2. Is the urchin getting enough to eat? Is there coralline on the glass/rockwork for him to graze?
3. Is anything - fish, crab, shrimp - picking on the urchin? If something was off and you correct it, he won't be able to recover if he's being harassed.
Do try and see what you can do. My urchin started dropping spines a few months back - I had no idea, but there had been an ATO mishap and the SG had dropped from its usual 1.025 down to 1.021 and Speedy nearly died after a few days in these conditions. I corrected the problem as soon as I found out, made sure he had food to eat and wasn't being picked on, and over a matter of weeks he slowly healed. There were days I was certain he had died - once he lay upside down on the sand for hours - but he made it through. Best of luck.
D to the P
New member
Exactly
Urchinhead
Member
I am sorry to have to tell you this but... Yes. Your urchin is dying. You may be able to move him to a QT tank and with ALLOT of hard work bring him back from the brink but generally when it drops spines its already too late.
Generally these things happen, as previously mentioned, by a too rapid salinity swing, some kind of copper based substance being introduced to the system, poor acclimation process, starvation in the extreme, or the like.
As a note going forward because I didn't see how long you had him or for that matter if you plan to get another... Make sure you very carefully drip acclimate him over at least a 45 minute period before introducing him to your tank to make sure he slowly matches up with your salinity.
This by the way is the usual cause of death in an urchin and it does not always manifest itself right away.
Generally these things happen, as previously mentioned, by a too rapid salinity swing, some kind of copper based substance being introduced to the system, poor acclimation process, starvation in the extreme, or the like.
As a note going forward because I didn't see how long you had him or for that matter if you plan to get another... Make sure you very carefully drip acclimate him over at least a 45 minute period before introducing him to your tank to make sure he slowly matches up with your salinity.
This by the way is the usual cause of death in an urchin and it does not always manifest itself right away.
Following on from this and because I'm curious.
One of the hitchhikers on my Live Rock was a sea urchin.
He's been in there for about 3 weeks now. Retaining all his spines (For a given value of he/she btw).
How quickly would I expect loss of spines? Does it show up within days? Weeks? Months? Have I passed the danger period and can assume that I have a happy inhabitant?
AD
One of the hitchhikers on my Live Rock was a sea urchin.
He's been in there for about 3 weeks now. Retaining all his spines (For a given value of he/she btw).
How quickly would I expect loss of spines? Does it show up within days? Weeks? Months? Have I passed the danger period and can assume that I have a happy inhabitant?
AD
I have had this urchin for about 8 months. It is in a 200 g tank with lots of coraline algae. (The tank is just over 2 years old.) There have been no change in parameters. The only thing I can think of is that the temp may have risen SLIGHTLY as it has been quite hot here. This has happened before and it has been fine.
As an update...I have moved it into the fuge and it has not dropped any spines in the last 12 hours. It is eating and moving around the fuge. We shall see what happens...
As an update...I have moved it into the fuge and it has not dropped any spines in the last 12 hours. It is eating and moving around the fuge. We shall see what happens...
Urchinhead
Member
In general its within days to about two weeks. Depending on the urchin if it is covering itself with camouflage then you should be ok as this is a sign of a happy healthy urchin. I say depending because long spines and pencils (pencils will eat your fish and corals btw) don't but Tuxedo's and pincushions do. Here is a photo of my tuxedo and his zoa colony. The zoa's love it btw. They get to see new places every day! :rollface: They do this in the wild as a form of visual and tactile camouflage against predation by starfish and the like.
In my old tank with my pincushion (he grew to the size of a tennis ball and was headed towards soft ball size) would pick up hermits and it was comedy gold to watch them passively sit legs extended (not struggling) while it cruised the tank. They would get a free ride and usually ended up in a place where there was something to nosh on.
Just be aware that Urchins are very strong for their size and can move rocks that would startle you when you see their size in relation to the urchin. Between my abalone and my urchin I get to wake up each morning and play the what corals are now ****ed and knocked over today game. :mad2:
Ultimately when I get everything just the way I want it I will glue things down but as of late I am just too lazy! 
Lastly if it does make it through it is a very efficient cleaner of rocks and glass so keep in mind that depending on the size of your tank you may need to supplementary feed it with Nori. A 1" x 1" piece placed near where it is foraging (it will extend feeder tentacles that look like antenna) so it can find it about once a week or once every other week should be ok.
Urchinhead
Member
Humm... That is odd. When you said all of its spines that usually means its on the way to being dead. Since you now mention that it still has spines you may be facing a sick but recoverable urchin. Another good sign is that its eating. Spine drops are usually a sign of stress and illness. It is usually associated with a rapid environmental change like salinity or for that matter a temp spike. If by slightly you mean a shift of 4-5 degree's quickly that could have done it.
