The Yellow Multi-banded Pipefish is one of the pipefish that doesn't have a "true" pouch that you see in Seahorses and in some Pipefish.
When the male carries eggs they will look as though they are just stuck to the under part of the belly in two rows, starting about the middle of the body and going back 1/2 down the tail. The males have a flat looking belly.
The females are much broader then the males and could be as much as an inch longer then males. They look very plump compared to the males.
By looking closely at the one you have you shouldn't have a big problem finding one of the opposite sex in the tank of a LFS.
Please make should that you follow proper quarantine if you locate one you want to add to your tank. You don't want to add a disease or parasite to your tank.
I don't know about the Yellow Multi-banded Pipefish, but there are many species of Pipefish where one sex is very territorial. The opposite sex moves into this territory for mating. It can be VERY difficult to add a male to a female's territory (or visa-versa). Fighting is not uncommon if there is not enough tank space for both.
Fighting may also occur if you add one that is the same sex as the one you already have.
Keep your quarantine tank available if this happens.
Remove both Pipefish and move some of your decorations/rock around some. This will appear to be "new" territory to both Pipefish and if they are opposite sexes more fighting can be avoided.
Chuck
