How to prun Hygrophila corymbosa?

Despite my algae problem, some of the plants in my 6-week old tank are 
doing quite well, the six stems of H. corymbosa I bought in the first 
week of the tank has grown out of the water and are in danger of being 
burned by the lights. They were only 10 inches tall when I got them and in 
six weeks they outgrew my 24" tall tank!

Anyway, I read the article by Erik about pruning various plants from the 
Krib WWW site, and he said that cutting the stems of H. corymbosa always 
caused significant trauma to both parent and "offspring" plants. Has 
anyone else had similar problem? What's the best way to take cuttings 
from corymbosa without interrupting its growth too much? What's the 
best length of the cutting, and where should I make the cut: at a leaf 
node, just below or above a node, etc? Thanks. 

 John Y. Ching (jyching at watnow_uwaterloo.ca)    |
 Pattern Analysis and Machine Intelligence Lab	| 
 Department of Systems Design Engineering      	| 
 University of Waterloo, Canada            	|