In regards to the cabomba I have never liked it do to the facts
that my fish always liked to tear it apart and mees up the tank.  However
my findings when I did grow it were as follows.  If it has enough light it
vetts a nice deep red color, and if it shy on light it gets both stringy as
well as a pale green color.  I did not think it was a real high level light
requiring plant as it usually grew well for me in low tech 55 gallon tank
with only a pair of 40 watt florescent bulbs on a 12 hour timer.