So, will SPS grow under LEDs? Take a look at these fun four photos:

Here's my orange cap in a 130g tank, growing up the front side of the tank:

A closer look of at least an inch of growth up the front glass... it was also attached to the back as well:

A top down photo:

And finally, the huge beast, out of the tank prior to surgery with a Dremel and a high performance non-breakable cutting blade: