I have several timers, have used them before but I just believe in doing as much by hand as possible.

I am afraid that the something will catch on fire, fall or damage my plants.

my flower environment has to be "opened" each day to allow ventilation so if no one is home the plants would be cooked in the grow tent.

Maybe there will be an electrical fire, or water from the plants dripped onto something and made a short.

My space which I have my flower tent is not light proof (so it is sealed up each night and opened each day, and with out doors open does not get good air flow

Oh so many fears. I have just decided to do it by hand. Which is why I am asking if fluctuations as I have described are good/bad and what other peoples experiences have been.