I use one to check on qt or hospital tank.
Adding a video cam is one of the best things I've ever done for my hobby. Gotta get a high quality one if you want good resolution. I travel a bit and I'm often in the office long days. being able to click and see my tanks, anytime, has not only been enjoyable but very relaxing. It ads a completely new dimension to the hobby - IMO
At night time, you see their eye reflections hovering about. Very relaxing.
I use one to check on qt or hospital tank.
I have the Nest. Not cheap though