How should I trim this plant gone wild?

I have a plant (see picture) that is growing about 1-2" a day... It is now way too long for the tank. Do I just cut the stem off that is growing so quickly and discard it? Or do I try to replant it?

PS I think this is a Hornwort, but am not sure. I am new to live plant aquariums, and I got 4 or 5 different kinds.

 

You trim the stem at wherever you like and you can either discard it, float it, or replant it.

 

You can cut the stem at whatever height u want and replant it, if you want to.
You can also discard it or sell/trade the trimmings

 

You trim the stem at wherever you like and you can either discard it, float it, or replant it.

It seems pretty happy in the tank - it is growing better than anything else. I'd hate to get rid of it if it can grow into another plant. Thanks for the advice!

 

It seems pretty happy in the tank - it is growing better than anything else. I'd hate to get rid of it if it can grow into another plant. Thanks for the advice!

No problem.

 

I think you can trim the plant lower than the height you want it, then the piece thats planted will send up side branches and grow more bushy, and you can plant the piece you cut off next to the original. I‘ve never done it with that particular plant, but with a few other stem plants it works well and the replanted piece grows roots very quickly, you end up with a denser bushy plant mass rather than a long straggly one.