What plant is this?

[Newtofish!]

I'm setting up a planted tank and just bought some new ones and they are currently in quarantine. Not sure what they are as they were just sold as "bunched aquatic plants" any ideas?

 

[Essjay]

It looks like Java fern. This should not be planted in the substrate as it has a rhizome which will rot if covered. The rhizome can be left on top of the substrate but it is too easy to accidentally cover it there. For that reason it is usually grown attached to decor.

 

[Newtofish!]

Thank you! I have taken them out of the substrate and they are floating free. Thankfully I have a huge bit of bigwood in my tank they can attach to