I have an Eshine Aquasun LED light i bought a long time ago for my biocube, wanted it because it was cheap and it had the sunrise and sunset feature which i wanted badly but didn't want to spend $500 bucks on one (Eventually did by going with a Maxspec).
Well long story short i upgraded tanks and had it laying around placed it in my sump and got a small ball of Chaeto, less than a month later i had a buckets worth (Got rid of it on the 24th) today is the 28th and i got half a bucket full of it again. i run the light 24/7, there is tons of water movement down there from a powerhead and also from the overflow. its growing so much that i have it growing on the sump walls.
If anyone is close to Rhode Island come see me, i am giving it away for free lol