I'm a bit baffled by some lighting recommendations...

[jaylach]

In addition to all the arguments pro and con regarding timers (I use them but will not press them upon others), there is yet another good reason to have a timer-

In many light setups, new and old, the on/off switches are among the most common things that eventually fail, often rather soon. Having a timer eliminates the need of manually turning them on and off, thus avoiding that kind of damage. In old fluorescent sets (which I still like and have some), the switches often fail before anything else. In new LED sets, the switches are so cheap (cheaply made) that they also fail, but replacing them is not as easy or cheap.

I can see that but does not apply in my case as one wall out behind my couch and close to the tank is connected to a wall switch and I just use that. Regardless, a good point.