Urchin Appreciation Thread/Reef Safe Urchins

[Mjl714]

Great idea for this thread. I also share your love for the urchins, fantastic clean up crew members. As you have indicated, while mine appears reef safe, it can be a bulldozer and is now slightly smaller than a baseball. Mine also gets a periodic visit into my refugium, which it appears to love. Below are two different looks of my urchin. I’ve had this urchin since May 2017.

 

[EricR]

I really like my "pink urchin" as the LFS called it when I bought it a while back.

...but,,, errr,,, uhhh,,, this is becoming a far too common occurrence:

 

[steallife904]

anyone notice these are becoming hard to find and if the LFS has them are a lot more expensive than they use to be???
I have had a tuxedo urchin for years in my 150. I want another but my LFS have not had any and said they are not coming in? Last time one did have one it was like 50 bucks!

 

[Snoopy 67]

Picked up 1 last week for $20,black & white.

 

[SlugSnorter]

all tuxedo urchins need tophats, this is a fact

 

[dado150]

Mine loves dragging the flat glass all over....

 

[Lividfanatica]

I am hoping to have a few long spines in my 310 with a handful of bengais. Fingers crossed I'll get to see some amazing natural behavior between the cardinals spawning/brooding and then the urchins hosting the young!

 

[All_talk]

I have two silicone seams on my nearly new, custom built 215, that have lifted and edges torn (thank you Planet Aquariums!!!) The Banded Long Spine has chunked away some small pieces of those lifted edges, but it's really not HIS fault. (thank you again Planet Aquariums!

True or false their ‘beaks’ can scratch the tank’s glass?

They wont scratch the glass but they can damage power cords and other plastics. I lost several power heads before I figured out who was chewing through to the copper wire. I love my Pincushion, so all my in-tank cords now have 1/4" wire loom covers, he still chews on them but the covers are easy replaced.

 

[undermind]

Just a few thoughts on urchin stings and pokes...

A successful envenomation from a Fire Urchin is a whole different category from a bee sting (unless you're allergic). Their venom will cause significant pain if you actually got properly tagged by one. I say "properly" because their venom spines are shorter than their long hollow spines that they walk on. So to become envenomated, you'd have to puncture a 1/4 - 1/2 inch or so of the long spines into you before you hit the venomous ones. Then you're dealing with a pretty solid sting.

Kings of Pain on History channel tested out a Fire Urchin sting on season 1, episode 6. They always describe sea life stings as being a different and "special" sort of pain.

I had a pretty special experience with a long spine urchin when I was 19 or so. I was snorkeling in Hawaii and had a surge push me hard into a reef rock. I instinctively put my hands in front of me and one hand went into a hole. I felt what seemed like an explosion in the hole and my hand was the center of it. Kind of like having a m100 go off in your hand (I've experienced that too - stupid human tricks). I pulled my hand out of the hole and it was a pincushion full of needles and a bit of a bloody mess.

Some highlights:
- several needles went through the space just under my fingernails with the tips going past my first knuckles. You could see the spines right through my fingernails.
- the needle tips oozed out a black fluid that you could see like a black dots under the skin. So you could tell how many spines got in and how deep.
- pulling spines out is a no-go. They just break apart in segments.
- the doctor at the hospital gave me the classic treatment orders: just pee on it.
- I was no shark attack survivor, but I felt pretty cool as an urchin attack survivor.

I love urchins. Long spines and Fire Urchins are usually my jam.

 

[CaptPatrick]

Could someone help me with an ID on these two? I got them awhile back when I was having a bad hair algae outbreak after raising nutrients to fight Dino’s. Tank seems healthy now but I’m nervous that there isn’t enough growth on the rocks for both of them so was going to give one back to LFS. If they are different species which would be best to keep for future algae control? I don’t like to get animals and then give them back or trade but I also don’t want them to starve.

 

[shakacuz]

my fuge urchin has a hat of chaeto

 

[trsmith18]

Don’t forget these beauties!

What is this? I must have one!

 

[TheDragonsReef]

They wont scratch the glass but they can damage power cords and other plastics. I lost several power heads before I figured out who was chewing through to the copper wire. I love my Pincushion, so all my in-tank cords now have 1/4" wire loom covers, he still chews on them but the covers are easy replaced.

This is not true, i had an urchin leave 3 circular scratches on my glass tank, i had to take him back almost immediately.

 

[davidcalgary29]

What is this? I must have one!

Oy, that's my fire urchin. It's without a doubt the most stunning invert that I've had. It's also, without a doubt, not reef safe, as it will eat whatever sabellids (feather duster worms) you have in your tank. Yeah, my first post was wrong. Now, it's possible that fire urchins just go after their hard outer tubes, but feather dusters are essentially defenseless without them and will just get eaten by other things in your tank. They're also detrivores, and not planktivores, and will benefit from the occasional meaty meal, which makes them quiver with excitement and move quickly towards the meal.

They also grow very fast. Mine has tripled in size since that picture was taken. Moral of the story: don't get one if you don't have a room for an 8" venomous beastie. Mine's in a four foot tank, but should probably be in a six-footer.

 

[undermind]

A few more Fire Urchin tidbits...

Mine came with a Zebra crab living in its spines. Super cool looking guy. A little reading told me they have a symbiotic relationship with the urchin.

However, a little watching showed otherwise.

I left the pair alone for a while but started noticing some strange behavior. The urchin kept climbing up to the highest point in the tank, a rocky overhang, and it would literally jump off. It would do this repeatedly. I was getting suspicious that the crab was irritating the urchin and it was trying to get it off if him. Eventually I saw the urchin was on the glass so I took a look at its underside where the crab was hanging out and saw that the crab was eating the spines of the urchin. It took out 25% of its spines. I hadn't noticed earlier because I hadn't seen its underside since the day I got him and the crab did some decent damage in 3 days.

Getting the crab out was interesting, but my welding gloves I use for my wood fired oven came in handy.

After some more reading, I found some info that conflicted with the symbiotic notion and saw that the crabs aren't known to kill the urchins but I suspect they must move from host to host in the wild which might not result in killing the urchins on a reef but here in captivity this urchin would have been dead in a few more days at that rate. Being the only urchin in the tank wasn't a good thing.

The coolest part is that those spines were fully grown back in just a couple days.

 

[All_talk]

Could someone help me with an ID on these two? I got them awhile back when I was having a bad hair algae outbreak after raising nutrients to fight Dino’s. Tank seems healthy now but I’m nervous that there isn’t enough growth on the rocks for both of them so was going to give one back to LFS. If they are different species which would be best to keep for future algae control? I don’t like to get animals and then give them back or trade but I also don’t want them to starve.

They both look to be Pincushions, what size is your tank?

I have had my Pincushion in a 47 bowfront for many years, even with a good sized cleanup crew, there is plenty for him to eat. But depending on you algae level I'm not sure I would put two in less than 50 gallons.

 

[Anemone_Fanatic]

Urchins are objectively the best CUC. What else is captive bred, reef safe, eats any algae under the sun, and has so much character? I will never have a tank without one or two.

 

[All_talk]

This is not true, i had an urchin leave 3 circular scratches on my glass tank, i had to take him back almost immediately.

Interesting, what type did you have? I have read that the pencil/rock urchins can dig in deep on rocks and such.

 

[Cantusaurus]

Interesting, what type did you have? I have read that the pencil/rock urchins can dig in deep on rocks and such.

Yeah, this was interesting to me since I have multiple rock urchins, and a Variegated Pincushion. Even the rock urchin never scratched my glass when eating.

 

[dvgyfresh]

I love urchins ! Feel like they are a must in any tank, reset biofilms on rocks clean up tank, and are cool as heck lol