looks exactly like subwassertang with the exception subwass would imo really dwarf this plant. notice the fronds are only about twice the width of the blue line on the paper. it is awesome that it fluffs up in layers just like in the link i provided also. it is much lighter and fluffier in the water too.
i have to be honest here guys. i'd love to get some photos of it in the tank but i'm pretty sure i can't considering where it is, tank growth and my awesome professional photography skills. heck i had the camera on a tripod with the room light, 2 clamp lamps and a flashlight just to get that second pic. after all that i still had to choose from dozen pics and crop it.
the wifey was kinda mad as i stopped her from reading a novel to hold the clamp lamps... lol. i thought that was funny, sorry.