I have a light meter that I use to dial in my height and dimmer settings. I set the height to where I’m getting the most even coverage, and then I adjust the dimmer to hit the number I’m looking for:
Seedling 350-500 umol
Veg 500-700 umol
Flower 700-1000 umol
Early in the grow when the plants aren’t filling the space, you can drop the light in very close; since you don’t need a wide coverage area, and then dim the light down to save some money. When the plants are mature and flowering and the light is running at full blast, I’m using the meter to dial in the height, in order to stay within +/-5% or so of the maximum.
BluMat seems to be one of the most popular options for automated watering. I used mine for a grand total of 3 days before going back to hand watering. I found it difficult to get it adjusted right and then it sprung a leak (my fault, not the system) and that’s when I pulled the plug on that experiment.
Using reflective material is a dirt cheap way to increase the efficacy of your light. Anything shiny will do. My favorite hack that I’ve seen on this site is gift wrapping paper.
100lb light assembly?? I use the 1/8” ratchet hanging hooks but I don’t know if they’d support that much weight. Is it old?