Okay, I went to the National Aquarium in Baltimore and I saw a tank with Banggai Cardinalfish and a Black Long Spined Urchin. The tank looked really cool, with the cardinalfish in the urchin's spines and everything. So, I would like my first marine tank to replicate that. What I want to know is the minimum tank dimensions for an urchin. I understand that they grow up to 12 inches in diameter, including the spines, so the tank would have to be more than 18 inches in all directions for comfort. I have a corner in my house that I'd like to put something in, as well. Here is a photo of the corner:

The max gallons I could get from that corner would be 61. Could I put a long spined urchin in a corner tank (33in x 36in x 24in)?

This post has been edited by n3ont3tra: Jan 24 2007, 12:32 AM

I have a long spine urchin in my 14G, I keep them for awhile and when they start to get too big I trade him in on a baby. The only complaint is that they eat coraline algae, but other then that they are a really cool addition to a tank!

I don't want to keep having to trade them in, though. I think that puts more stress on the urchin than there needs to be, and besides, I want a larger one.

i went to the baltimore aquarium on sunday! that tank with the urchin and cardinals was so cool. i loved the tank with like 25 yellow tangs 5 blue tangs and every other tang in the world.

I liked that too, I love yellow tangs. Could you take a guess on how many gallons the one with the urchin was?

it looked about 20 gallons but the cardinals were pretty small and will probley get to big for that tank cause there were 8 or so of them. I'd say if you want the Black Long Spined Urchin mabye a 30 - 50 gallon. the 33in x 36in x 24in sized tank you talked about sounds good for him, how many cardinals are you hoping to keep?

Baby cardinals will live in nems. as you have seen.i would say that most long spines will not grow to the size of ski's head (Wich is huge by the way) and that a 30 gallon breeder would be a good size.

Corner tank... Perfect

Mkay, thanks for that, I have a good idea now of what the tank will be like... Thanks again!