Itty Bitty Diadema urchins?

[christyf5]

Originally Posted by kari

Beverly,
Their purpose is to help one hone their attention skills. I've already moved up to Fire Urchin level .

[Delphinus]

Because they're kewwwwwwwwwwwwwwwwwl!

No seriously, they're neat. Sure they knock things over but so do snails, so .. not really anything different there. In fact, if there's one profound lesson I've learnt as I near the 10-year mark in the hobby... glue those dumb frags down. They grow better anyhow if the isn't a hint of a wibble at the base.

And yes they do work on pest algaes as well, although it seems different species have different preferences. I had this sort of fuzzy brown algae that was really tough in texture, blue tuxedo urchin cleaned it right up. And although it's a coraline muncher, thing is, they actually help spread the coraline by spreading the spores around. So you have new coraline popping up much faster IME. So it's not all bad.

I have a green urchin (looks little like a tuxedo type, but a little different) and it is doing a number on the bryopsis I have in that tank. I couldn't be happier. And it is *so weird* to see this thing up on the glass, picking off little bits of hair algae or whatever ... with its "belly button mouth" ... LOL.

And why a diadema? Just for something different I suppose. But they also don't have a habit of dressing themselves with rubble like the globular types do. (Actually I don't mind the habit of "decoration" .. it helps me get at the little bits that I ordinarily can't get at... a very helpful janitor!)

Also when I was in Hawaii the diadema's I saw there had an incredible blue sheen to them. I can't describe it and I'm not sure if it showed up in the pictures very well but it was very neat to see. Ever since then I've sorted wanted to try one of those as well.

I dunno, it's like other ornamental things. Like, why CC stars, someone once asked me why I have those. The answer is sorta simple, "they remind me of the ocean."

Hope that clarifies some of the madness...

Originally Posted by Beverly

These may sound like dumb questions, but what is the purpose of having an urchin in a reef? I know they will eat coralline algae and sometimes knock over corals, which makes me not want to keep one. Do they pest macroalgae as well? And why a diadema urchin as opposed to other urchins?

TIA

[AndyL]

Do a search on the florida / caribean projects to reintroduce diadema to their reefs (>90% lost due to an epidemic decades back). Little question as to their effectiveness at reducing annoyance algaes / macroalgaes, and reducing silt deposits on the reefcrest. Allowing corals to repopulate the reef.

In my little 3g - (s)he's making a massive dent in the bubble/hair algae infestation...

Like Tony said - the tuxedo / pincushions are rather annoying in relocating your frags (especially zoos) for you.

[tomini]

anyone know if they still have some more?

[Ruth]

They definately serve as a not too gentle reminder not to plunge your hand into the tank without thinking! I just finished jumping around holding my thumb because I did just that and managed to ram a spine up my thumbnail
They do encourage the spread of coralline - particularly on the glass viewing areas of my tank.
Right now I don't like mine very much as my stupid thumb (yes attached to an equally stupid person) is still throbbing but most of the time I find it a very interesting creature and they do a good job on pest algea IMO. If only it would get a taste for aptasia and majono!

[Delphinus]

Well, a month in, and not so itty-bitty anymore. 1.5" tip-to-tip at purchase time, now easily >3".

Here are some pics, you can sorta see the blue spines I was referring to earlier. They vibrate like CRAZY.

Definitely neat stuff ...




Added bonus of catching at least 3 pests as well in these shots.