Budding hydroponics problems

I setup the hydroponics set a couple of days ago, so that my pothos plants could root and be ready for the summer. The system is quite bright and the times for the light to get turned on are all messed up and I can't be bothered to fix it as it stands, but I've surrounded the device with foil so it doesn't scare the bejeezus out of me or irritate me when I'm in my living room. The idea is to take out the cover whenever anybody is over so it does look as wretched.

However, there are uhhh budding problems that have been noticed. Namely, some of the leaves which were previously slightly browned are growing their 'burned' areas, and even some of the fresh and bright young leaves of the plants I care the most are showing signs of light and heat burn, leading me to wonder if it's too much light for them. Because what's the point if I can't help them with the device? I don't want to manually control the timing of the lights as it's not a viable strategy that can last long, and the light is kinda' hard to turn off and just let the pump work? I will test this setup out for a week or two, and if this still leads to similar death and disease, I'll instead plant those cuttings into water bottles and put 'em against the window sill land plant tomatoes in the device instead. But still, it's unclear why they're dying and browning because shouldn't these tropical plants go absolutely gaga for light or something?