How do you sex a Pipefish?

You might want to put up more pics. From those pictures, they are not even the same species. Where did you get them from? Either way, what is on the left is a male, can't tell anything about the one on the right. Pipefish tend to get along just fine. There are some exceptions, but those you have, are not fighters. Just a couple more pics would be fine just to make sure it's not angle deception.

 

I will try and get another pic. The green one tends to move to a certain position when he sees me. Making it hard to get pics.

 

The species is Caribbean Pipe Fish (Syngnathus caribbaeus) . They come in different colors. From what I've seen the colors are green, brown and red, white with gold and copper. You can't see the details from my photo but they have really nice contrasting colors. They are both the same species just different colors.

 

I'm not looking at the colors at all.

Are they in a bowfront?

Did they come from Florida?

 

I believe they are both from Florida. They are in a quarantine tank right now, it's not a bowfront.

 

The one on the left is def a male.