If you have live plants, you'll want between six and eight hours, less if you have plastic plants.
Whichever, arrange to have your lights on when you're there looking at the tank. My living room tanks are on between lunchtime and about 8pm; the tanks in my bedroom are on between eight and about 2am, 'cos that's when I'm there
Whichever, arrange to have your lights on when you're there looking at the tank. My living room tanks are on between lunchtime and about 8pm; the tanks in my bedroom are on between eight and about 2am, 'cos that's when I'm there

and I can vouch that it is frustrating! I'm not quite clear on the light issue but it seems like you could leave that light structure for a while (if the wisteria seems to be dying, up the wattage). I'm sorry that's such a general answer...probably someone on here can answer you better.