I have a Beamswork Hi-lumen 36" for a 36" X 18" X 24" high and I am sure my lighting is low, here is the specs, to give you something to compare :
I grow, limnophila sessiflora, egeria densa, crypts, which are doing great.
Hygrophila polysperma not doing great, growing but lower leaves falling, indicating the plant needs more light.
129x HQ 0.2W LED (121x 10000K daylight, 8x 460nm Actinic)
Note : mine is made of 0,2W leds and is somewhat more powerful.