glxtrix;826724 wrote: They say not to run at night due to pods coming out more, you could potentially harm the population...I've never really seen a huge decline in my pods and I run uv 24/7...have for many years. Keep in mind UV adds a good bit of heat to your system. And a large 300+ system, you're going to need a nice size UV setup. There are pluses and minuses to running UV, I say if you don't have any issues, and everything seems fine, I wouldn't worry about that expense.