I dont have any sites, but I have read they pretty much need a tank of there own because there slow eaters and if you have something else in there they can starve. Are you thinking of keeping them?
the only ones that will survive in a 12g tank are dwarfs. I would not recommend dwarfs b/c they require live food. so, unless you are prepared to do that I would try a bigger tank and get other kinds of seahorses that you can feed frozen to.
I see in your descriptions at the bottom, you have an empty 125g. you said in a post a "12g" tank. don't know if this was a typo are you really want a 12g for seahorses. in any event, go w/ the 125. get some cool macroalgae... Marine Flora!, Your source for Coral and MacroAlgae! floridapets
I've got a 55g w/ two Reidi's that I bought at a LFS. A 35g hex is home to two Erectus's I purchased from dracomarine. Love them all!! buy captivebred ones in case you didn't know that. Sea Life Inc. sells SH's but they are wild. research, research, research.....
good luck!
Thanks to all the replies but I have decided against the ponies for now. Partly because of thier local availability, being none, and how difficult they are to keep. Thank you for your input.