@rives & Dave.
Good point rives.
I, as a matter of fact only help friends with their indoor projects, but am a guerilla farmer myself for obvious reasons.
For us it is best to visit my friends places as little as possible and let the blumat's do the work for me.
Basicly I only take care of raising the lamps and do an occasional feed once a week, starting when they are in full bloom.
My favorite setup has got one cubic meter of soil, 2 blumat tensiometers (one up and one measuring at the bottom) has got 3 x 400 wtt hps above them and is real easy to maintain this way.
Blumat auto watering & blumat tensio meters DO seem to work for us Dave.( But note that I am an exp, senior grower wich might make some difference)
Sounds like you have a similar setup to one Ive been wanting to do. I was considering filling a large rectangular bed and outfitting it with various suction lysimeters and Irrometer Tensionmeters so I can constantly monitor soil solution EC, and soil moisture. Im wanting to run 3 600's over this bed.
Im tired of only being able to monitor a couple of containers at a time. One large bed, or multiple smaller beds with the right equipment would be better.
If I ever get around to getting it setup, Ill post some pics.
Im unsure why one wouldn't want to use a tensionmeter along with their blumats. Using the tensionmeter values along with visual inspection of root health would only further lead to an improvement with blumats, imo. Its a very affordable tool as well. Id like to see more people using them.
