J
Jalisco Kid
Guest
That depends on your wattage and I think if it is broad or narrow beamed uvb. My friend runs his 6 hrs in 12 while my narrow beam9100w) peaks out at 310nm seems like 4 hr does ok till week 8 of 10 then I bump it to 7-8 hrs. I had some uvb made for me that peaked at 285nm at 39w. I would rather have 3 39w then 1 100w for dif source points. JK