I have recently started up my new hydro system using a drip ring setup. Turned on for the first time, after everything was checked, nutes etc and then this morning, when I checked the water, it looked like there was an oily film on it. It went when I mixed up the water, but I'm still a bit worried. Is it just the nutes I added? To a FLOGROW 500 (17 litres), I added 120ml of IONIC GROW. Any advice please?
