evil carnivores of death and destruction

[pinkie]

I still don't recommend urchins with puffers what so ever. I was looking for a solution to my minor algae problem in my semi-aggressive FOWLR tank and decided to try urchins. I first tried pincushion urchins. My dogface (who is still quite small at about 4-5") simply took his time and chewed down all of his spines. He made for a tasty snack in less than a day.

I then thought longspine urchins would be best, given the longer sharper spines and poison. Same thing, the Dogface had absolutely no problem eating him. I thought maybe it was because the urchin was too small, so I got a pretty massive longspine, who actually turned out to just be a bigger snack for the dogface. I actually went down the day after I got the big urchin and saw the Harlequin tusk with a pretty big chunk of the urchin in his mouth with full length spines sticking out of his mouth, which he decided to swallow. I thought he would be a gonner for sure, but 3 months later and he has no problems at all.

I do currently have a pencil urchin, which to my surprise hasn't been touched in the 2-3 months I've had him. However, I am expecting him to be toast in the near future which is why I am not getting any more. However, if he lasts for another few months and the other fish still have no interest in him, it may be a viable option.

[roka64]

Ok, that's awesome experience (not for the urchins), thanks for sharing.

[Kurt_Nelson]

Originally Posted by amp123dime

I acclamated the urchin about 15 min from the time he was bagged up at the fish store. with about 1/2 tank water and 1/2 store water the container I had and the amount of water from the fish store wasnt enough since the urchin had such long pines. I then used airline tubing to start a drip and let it drip for about 45 min. then dropped him in the tank.. ...

OK... if I'm reading this correctly, as soon as you got home you put water from your tank immediately in the container with the urchin, to double the amount of water in the bag from the LFS. THEN, you started a drip for 45 minutes.

If that's the case, you didn't really drip acclimate and that could probably be the problem. Immediately doubling the amount of water from the LFS by using tank water - depending on the differences between water parameters - was probably a pretty good shock to the guy, and kind of defeated the purpose of the drip. In fact, the old "dump a shot glass every 15 minutes" method is probably a gentler method than immediately doubling the water volume.

Small little 1 or 2 quart plastic containers with graduated lines, like you can buy at paint stores or at hardware stores, are great for acclimating. The graduated lines totally take out the guess work of how much water is in there, and when the amount doubles, etc.

[MT79]

Small little 1 or 2 quart plastic containers with graduated lines.. take out the guess work of how much water is in there, and when the amount doubles, etc.

Great idea Kurt, I'll have to pick one of those up.

[Kurt_Nelson]

Originally Posted by MT79

Great idea Kurt, I'll have to pick one of those up.

Oops... just looked at the containers I was thinking about. They're 2.5 qt and 5 qt containers. 1 quart would be a bit small, I'm thinkin'.

[squawkbert]

Even if you acclimate slowly, urchins are one of those "diagnostic nightmare" animals. They look fat and happy until they drop dead, melt, shed... or whatever. Because of the chitin/exoskeleton etc. they're one of those animals that's usually well on the way out by the time you notice that anything at all is wrong with them. Any animal w/ an opaque exoskeleton (many arthropods, all echinoderms, tunicates, many mollusks), any animal whose mouth is not visible when it's eating (any echinoderm, many gastropods) fall into this category because it is really hard to have any clue as to how they're really doing.

With crabs, shrimp, anenomes and some bivalves, you can at least watch them eat.