Urchins: Love ‘em or Hate ‘em?

[Vette67]

I have 2 rock urchins that have been in my 180 for about 15 years. They just move from pane of glass to pane of glass, cleaning off the never ending supply of coralline. They do a pretty good job keeping my glass clean. As long as you have a sufficiently well growing coralline algae population, then urchins are easy. But they are voracious eaters. Don't underestimate how much that little ball of spikes can eat.

I used to have a longspine in my 180, but it got to be too big and mowed over everything. So that one is banished to my 75, where he has free reign over my chaeto, and does a pretty good job keeping that well eaten. My recommendation for a long spine, is to keep in mind that they grow big. If you aren't ready to house an animal that can grow to the size of a basketball, then you should look for a different urchin. That cute little spike ball at the LFS will grow big pretty quickly.

 

[zert11797]

I hate them they ruin everything lol. They move everything too much

 

[McCarrick]

I have a halloween and a tuxedo.
They did not touch hair algae when I had it, its all gone now.
They do eat alot of coralline though which helps alk consumption some.
I have had both about 9 months now and the back wall was solid coralline and now it is not.

How big is your tank? I saw a small red tuxedo urchin at the store the other day (about 1inch across) and have been thinking about it. I have a 29 gallon tank. I'm in the uglies stage right now and am hoping to get rid of excess algae.

 

[laverda]

Love the tuxedo urchins. Just won't be able to have them acrylic tanks (and/or plywood) and urchins don't mix!

I have 5 urchins including tuxedos in my current acrylic tank for 4 years now and my previous acrylic tank with no signs of any damage to the acrylic ever. Power cords are a different story, as I have seen damage on them. Nothing to serious though. I suggest slipping some spiral wire wrap over cords if concerned.

 

[laverda]

My long spine will definatly munch on SPS sadly as it is really cool to watch otherwise. I think it may be because I don’t have enough algae for it to eat. I do feed it nori fairly often.

 

[X-37B]

How big is your tank? I saw a small red tuxedo urchin at the store the other day (about 1inch across) and have been thinking about it. I have a 29 gallon tank. I'm in the uglies stage right now and am hoping to get rid of excess algae.

120

 

[Doctorgori]

both:
hate that they absolutely ruin coral placement even when you thought they were glued down, also they remove purple algae allowing the faster growing ugly green type to take over
love that they also remove e a lot of ugly green algae

 

[Timfish]

Love them! They are critical for a succesfull reef IMO. They also help feed corals. Read Forest Rohwer's "Coral Reefs in the Microbial Seas" to see thier role in maintianing healthy reefs in the Caribbean. See also Martin Moe and his research. and here's videos of urchins feeding corals.

 

[Reefs and Geeks]

For me, they are great algae eaters, however they will pick up healthy snails and carry them around until they starve. I always liked them untill I added some snails to the tank. Way too much of a hassle to deal with and I wouldn't buy any more because of that unless they were my only CUC.

 

[Crashnt24]

I had two long spine urchins for 4 years. They are great algae eaters. I got rid of them though because they got so big. They ended up growing to the size of a soccer ball. Debating getting another small one since I upgraded my tank.

 

[G Santana]

Love how they look but they are like runaway bulldozers beautiful, performance driven but wrecking crews with spikes lol

 

[Jeremy K.A.]

I LOVE urchins, I think they're incredibly cool and fascinating. However, they're bulldozers and move frags etc.

I have a Pencil urchin which so many people have said is NOT reef safe but I have never had any major problems with it. Very rarely it will eat small chunks of Kenya tree, but other than that it's an outstanding citizen lol. They're kind of like any addition to a tank, there are pros and cons

 

[Jeremy K.A.]

Love them! They are critical for a succesfull reef IMO. They also help feed corals. Read Forest Rohwer's "Coral Reefs in the Microbial Seas" to see thier role in maintianing healthy reefs in the Caribbean. See also Martin Moe and his research. and here's videos of urchins feeding corals.

this is so awesome! My pencil urchin has done so before but it's presumably male because it was just white milky cloudiness so I imagine it was sperm unless pencil urchins have incredibly small eggs

 

[ajjw0828]

If you have a starfish beware. My blue starfish ate my urchin and then died.

 

[Timfish]

this is so awesome! My pencil urchin has done so before but it's presumably male because it was just white milky cloudiness so I imagine it was sperm unless pencil urchins have incredibly small eggs

Thank you!

It would have been sperm or eggs, gametes are really tiny and they have slight positive bouyancy so they'll float. If it sinks it's poop.

 

[Timfish]

If you have a starfish beware. My blue starfish ate my urchin and then died.

Sorry to question you but my expereinces have been quite the opposite. How did you determine this? After all commonality is not causality and blue starfish, I'm guessing blue linkia, aren't the hardiest animals. And considering they are both echnoderms I've got to wonder if there was something else going on in the tank that affected both of them?

I've had this Blue Linkia in this thread and this Diadem sp. urchin together since 2007. It hasn't been as long but there's a royal urchin in there also.

 

[ajjw0828]

Sorry to question you but my expereinces have been quite the opposite. How did you determine this? After all commonality is not causality and blue starfish, I'm guessing blue linkia, aren't the hardiest animals. And considering they are both echnoderms I've got to wonder if there was something else going on in the tank that affected both of them?

I've had this Blue Linkia in this thread and this Diadem sp. urchin together since 2007. It hasn't been as long but there's a royal urchin in there also.

Might have just been the starfish I had or it could have been something else. I will say they were constantly rotating around the tank from each other. Seemed like the starfish was chasing the urchin, but I don't have anything to back it up. All I know is one morning the starfish had the urchin cracked open and was eating it, then the next day the starfish was dead. I have an urchin now and would like to get a starfish so maybe I will add one and see. If they chase each other I'll just throw one of them in another tank.

 

[Key-tie]

Even though I love my urchin, they are ruthless hunters in addition to being great algae eaters.
My pincushion urchin already got 1 of my big turbos...
And now he got hold of the other.
He is, right now, peeling the turbo off the glass to eat him.
I could NOT get them apart without hurting/killing maybe both.

 

[Key-tie]

He now has him, and the snail is as good as done.
I tried giving Archie a piece of krill to let the snail go, and he just shifted, ate the krill, never released the snail, and is eating the last turbo now.
Archie will NOT get any more snails to eat.
The turbos were going on 2 years old and went from the size of a dime to bigger than a golf ball, until the urchin found em.

 

[Brit’s Fish]

It’s a love/hate relationship for me. I do like pincushion and tuxedo urchins, but my pincushion urchin constantly picks everything up or knocks things over.
He also likes to climb to the top of the glass to “spread his seed” like clockwork after every water change.

He picked up my tiger conch the other day... poor guy looked a little concerned.
These pictures are a good representation of everything he constantly carries around.