What is the secret to urchins

[Stomatopods17]

I've never had issues with acclimating urchins.

I've even bought rocks with hitchhiking ones (as in, they weren't even submerged, at all) that lasted me for years, knowing what species you were using would help.

I will say acclimating them in the same water as mushroom corals isn't the best idea, especially if the water has a lot of the 'mushroom juice' chemicals in such a small space. In a tank/ocean that stuff gets filtered/diluted but in an acclimation space its a soaking poison chamber.

My acclimation method is float for 30 minutes (15 is too short IMO), and I don't drip, I just dump some of the water out, and scoop a little water, pour more out, scoop, pour, scoop, pour, etc until pretty sure at some point the water is 100% rotated with my tank.

A lot of the urchins we get in this hobby very frequently get trapped in tide pools, so I'm not 100% sold on them being that sensitive (otherwise the water in the tide pool evaporating (salinity spikes) then suddenly being reunited with the ocean would all get shocked and die) and even if they are its a slow reversible process (spine loss usually).

My only assumptions for OP is bad supplier (condition they were in prior to shipment) or possible poisoning from long acclimations. The most recent one sounds like its best to give it time, lethargic behavior and spike loss for a new urchin is normal, they're stressed and they shed and regrow spines all the time.

 

[bj274]

Has he been losing any spines? How is the algae situation? Do you have massively long GHA? If so, I wouldn't expect him to begin feeding on it until you chop it all down to short hairs. If you don't have much algae, you might have to try different types of supplements. Mine knocked out all of the algae (assist from the turbos). I found it would not bother with Nori, but it happily eats a broken piece of algae wafer.

He doesn’t appear to have lost spines yet, but he is not moving around at all. I have really light colored, almost see through GHA, but he’s not moving to even try to eat.
I moved him last night and he seemed to settle in the sand a little but hasn’t budged since.

 

[flashsmith]

I always thought urchins were easy. I love them because they keep my tanks devoid of Coraline.

 

[PeterEde]

I always thought urchins were easy. I love them because they keep my tanks devoid of Coraline.

I like the coraline. Easy to see where the urchins moved over the rocks at night

 

[NanoMixer]

I've read this as well, taking a more aggressive approach with the sensitive inverts, it's definitely counterintuitive. The science behind it, if I remember right, is they are so sensitive once you add together parameter changes during transit (even just a short trip from the store) with a slow drip added on top of it causing micro changes and not allowing for much turnover in the bag water, it is continuously shocking the animal with those smaller changes.

So, with less "shocks" being ideal, what Jojo's LFS advised with the 50-25-25-25 or going all out like Twenty's LFS recommended and just chucking them in after temp acclimating this seems to work better for them.

This is exactly what our local reef store owner recommends and it has worked with all of our sensitive additions (Red Bell’s Urchin, tuxedo urchin, BTA, green slimer acro) to our 20g nano. He advised that the temperature fluctuations within such a small amount of time (store to bag, bag temp change during transit, temp instability in acclimation container), while leaving them in water that likely had a spike of ammonia during transit, is far more stressful than just putting them in after temp acclimation in the bag. He’s been in the business for over twenty years and has a dedicated reef-only shop. This is the advice he gives to everyone who purchases from him. I think if you’re getting one shipped, definitely follow the online retailer’s instructions so you don’t void warranty (some also use oxygen permeable bags that you shouldn’t float), but if buying locally, do the ol’ bag float.

 

[flashsmith]

Well.. I've just temp acclimated and dropped them in. Never had issues with them dying soon after. They seem pretty hardy to me. The shortest lived one I've ever had was 2 years. I have some now going on 4 years. I only use them to keep Coraline out of my tanks. I hate the look of it covering everything in my tanks. For that they are phenomenal.

 

[cyclone21]

I also have never had any issues with them. I actually bought 10 urchins to help clear my 220g reef from algae (newly cycled tank) I have dinos or crystophytes in it presently. They are actually helping to remove it. I acclimated them for about 20min then dropped them in. They are all still thriving. I do make my own rodi. But as far as being out of the water... mine come all the way to the top of my tank sticking out of the water occasionally

 

[ESABOE]

Very sensitive to changes in salinity. My first tux started losing spines and died after a water change with a batch of saltwater I got from the LFS that was at 0.038sg--my fault for not checking their water myself. LFS employee told me my corals probably loved all the extra Ca/Mg. Ordered a RODI buddy that day and have been making my own saltwater since.

I get mine from ReefCleaners. For the tux urchin, I was instructed to temp acclimate in the bag, then add 50% volume of tank water, then 15 min later 25% volume 4 times at 15 min intervals. Tux seems to be happy 5 months later.

I get aqua-cultured ones. My LFS had some Tuxedo in stock, and had been in their tank for 3 months so we knew they were healthy. I did wait till I had some detritus/diatoms and other goodies in my new tank before I I got two of them. They are thriving so far. I leave little sections on the back wall that I don't scrape just in case I don't have enough for them to eat. But they have had plenty so far.

I did the same exact acclimation as JoJo.

 

[PeterEde]

I've not actual bought any urchins but have 5 in my tank now
Longspine I had since my first piece of live rock 2.5 years ago. It was about 3mm when I first found it.Recent live rock got me 2 decorators and another piece got me 2 pencil urchins. All doing well.
This is the longspine