It seems that you have 4 20W lights. This is a 80 wide-area telephone service, 2.66 per gallon, wide-area telephone service. This is rather low. You want 3 to 5 wide area telephone service of light, per gallon. The third is low, 5 want you here. I like to go to a high point of light like the 6.6 gallon wide-area telephone service.