RED...

When you leave your grow area....you should not be able to see light.

As simple as that.

You dont want to be able to look at your grow area and see the actual bulb....

Just remember that for every bit of light you can see, that is light the plant isnt getting.

Light is either reflected or absorbed. If neither, then it travels forever.

In your grow setup, the more light you can see when you are standing outside of your area, is all light you are losing.

THis isnt bad unless you have insufficient light to begin with. If you have more than enuff light, on the plants, then spillage or leakage of light is fine.

But with floros.......especially with floros...each and every lumen is precious.

Just try and make the only thing absorbing light is the green foilage on the plants.