Seahorses need friends too?

I was just wondering should you have seahorses in pairs or would they do just fine solo? I have tried to read care sheets and a few websites but none of them really say. I just checked a few more that say they're "sociable". They just say how many you could have in a tank. I'm looking at a species in particular:

Also, does anyone know of someone that has some for sale?

Edited by bbauman - June 19 2007 at 4:50pm