Mine have a routine but its only because its my routine. When I wake up and after I brush my teeth and all that stuff I feed them then around 9pm I feed them dinner cause its right when Im getting ready to relax so I want everything done.
I think it's important to have a good lighting routine if you have plants. For the fish however, you don't really need a timer. I usually feed in the morning, and at night. Which is usually when fish eat in the wild(like you go fishing in the morning and at night, never in the afternoon.)
I tend to feed once daily sometime after 5pm, but it varies greatly from day to day and no problems have occured. As for the lighting, there i no routine, apart from once it goes on its on for 10 hours solid.
The only thing that is routine for my fish is the lights as they need that. Everything else I do what I can to not have a routine, keeps things interesting for them I guess.
They do a rather fetching syncronized swimming routine if I coax them enough
I don't really have a set schedule that I follow. I don't feed them every day, and it's always at different times. The only thing that is always constant it the lights as they are on a timer.
Lights are all on timers, otherwise there is absolutely no routine as for feeding etc. Sometimes they'll go a day or 2 without being fed, other times they'll be fine a couple times a day. I also mix it up lots, never feed them the same thing twice in a row etc.
My fish are not on a rigid routine, because I'm not on one.
I usually don't put their lights on until noon or later because they are often on until late at night, and I usually give them 2 small feedings during the day. I feed my fry microworms so they can eat as much as they want, whenever they want.
Other than that, water changes and tank cleanings are done as needed which is around every 5 days lately, but this changes too depending on the needs of my most heavily stocked tanks.