I've seen this in some folks' dart frog tanks and once in what may have been the most unkept, pitiful brick and mortar fish store I've ever seen, but never had it happen myself. That is really cool looking. Sometimes I wonder if we don't get the full potential of our plants because we try to make them conform to what we want them to look like or how we think they should grow rather than just letting them do their thing.
WYite
The one thing that irks me when talking about a planted aquarium...
Always when algae starts to grow, one of the first solutions is to reduce the photoperiod as having the lights on too long will mean there is too much light and that is what is causing the all the algae.
Or have a 'siesta'
While either method may be a part of a solution, I won't condone it simply because it will force plants to grow like days are shorter, i.e. winter growth.
Obviously someone else's aquarium.. but whatevs.
I am pretty sure virtually nobody gets the full potential from their plants. Because full potential would require just far too many ecosystems we are unlikely to provide them all.