My main tank is a 40b, co2 injected and is located in my dimly lit living room. I like having the lights sitting on the tank rim to help keep light out of everyones eyes when we are watching tv etc. Would it be a good idea to run 6x21w no tubes? I already own 2 2x21w fixtures but im debating if this is enough light for me. It comes down to 6x21w t5no on the rim or 3 t5ho tubes hung above the tank.
Ps. My substrate is about 14to15in from the rim.