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Any stem plant can be trimmed in the same manner (Anacharis is a stem plant too). You can replant the top as a way of increasing the number of plants in your aquarium. Eventually the bottoms will get ratty enough that you'll want to pull them and just replant the tops.
I've been doing that with my large leaf hygro. Cut a piece, pull the bottom bit out and plant the top bit. In 4-5 weeks I have leaves hitting the top of the tank again, and the upper cuttings always look nicer than the lower bits.