Marshydro Sp3000

I have 2x marshydro sp3000 in a 3x5 ft grow space .
Is that too much light for that kind of space. I have 6 plants in them .?
Can plants get too much light and cause stress.?
Thanks in advance

those have dimmers on them dont they? i just heard good rule of thumb is to keep them 18 to 24 inches away