First time hydroponics guy here. I have a AeroFlo 36. I started from seeds (Sucrine Lettuce) 21 days ago in Rapid Rooter, just planted my 3" plants with clay pellets in 3" net cups. I have adjusted my downspouts so the water level is 1/2" above the bottom the the net cup. The root strands are hanging slightly beneath the bottom of the cup. I have 600 watt Metal Halide bulb about 4 feet above the plants.
I'm using General Hydroponics nutrient Flora Series, right now since the plants are so small I've started with 550 ppm (1 part micro 1 part gro 1/2 part bloom) as I get growth will bump up to over 1000 ppm.
So here's my questions; How far off the plants should I have the light? at 4' the leafs are not warm to the touch nor do they appear dried out. I'm curious if I can get better growth with the light closer?
Anybody see any problems? Please feel free to comment on my set-up.
Sounds like a nice set-up. The light can definately be closer as light intensity loss doubles for every foot of distanece. I keep my uncooled 400w about 12-16 inches. A 1000 should never be closer then 2' from what I have read. I believe 2' for a 600 is relatively safe and you will get better growth. I read a physical test description that putting your hand at the distance you want and not feeling excessive heat after 60 seconds is safe. I have never used that approach, but I do try to feel the intensity around the light sphere to see if I am pushing too close. I hope that helps and good luck.
I lowered my light to 24" above the tops of the plants. I've enclosed a pic of my set up thanks for the help! They seem to be growing noticeably by the hour....