I think Ive been succinct to the point of obscurity here ... I responded to the post about cutting back Vals by saying "dont do it". What I meant was dont cut the tops of the leaves off. If you want to control the size of the plant take the whole leaf out from the base (as mentioned by several people already). Paul, are you sure you have a Valisneria plant? Ive never heard of one or seen one with 2 m long leaves ... perhaps its Sagittaria instead? dave