Water changes I try to do weekly, every Friday or Saturday but that can be at any hour of the day from 9am to 9pm. Lights are on a timer so they come on around 10am and go off at 6pm, except the Kuhli tank where the lights only come on from 11pm to 3am.
Food is random which keeps them from expecting to be fed and getting lazy. They get fed on a semi-regular basis of every 3-5 days, depending on my schedule and how much/what type of food they were last fed.
Everyone's pretty healthy and happy, if sometimes grumpy when they don't get their preferred food (RTBS only takes frozen now).