Water levels and keeping roots in the dark

Hello it’s me again the Newbi,
I know that the water has to stay below the net pots in DWC and let the roots reach down to it , but how do I check the water levels without exposing the roots to any light?
I have covered up the holes that are not in use to prevent light from getting in , but I am not sure how to make sure that I have the correct amount of water without exposing the roots to light ?

@Newbrn this is when you should have a reservoir. You can check the levels with out exposing the roots.
It’s not a deal breaker to exose the roots to light. As long as it’s not constant.


The roots are hanging down about 1/2 inch.
I just don’t want to let the water get too low or put too much in. I am growing DWC in a grow box that is 4ft tall 16 inches wide and 9 inches deep. The bucket is small of course and it is difficult to see inside it in order to tell how much water is inside.