Why not run ultra high light refugiums?

[Scuba_Steve]

I run 2 par 38 led grow bulbs using reds and blues

 

[R_Mc]

Can you elaborate on standing stalk SM? My new growth always starts white during periods of high growth - the new growth colors up 1-2 days later.

 

[SantaMonica]

Standing stalk is the amount of algae existing. White areas are the growth compartments of scrubbers (if they are colored white) to reflect the most light.

 

[natereinhold1]

I used to run a 250w mh and pc combo over my stock tank fuge and I had great growth (I feed a lot too) now in my jbj 28g, I modded the overflow chamber into a fuge and ive been using a 16x1w w/optics 10k led system right on the back glass shining throught the side so less than an inch away from the algae and as long as I scrape the glass once a week I got great growth until I started carbon dosing, now its all dying away because it doesnt have enough nutes to grown