First grow: Mephisto Sour Stomper, 70/30 Coco Perlite

First grow so I don’t have too much to base my progress off. I believe I had my lights at too low of an intensity to start which resulted in some minor stretching. I increased the light to 15 DLI which seemed to stop the stretching. I also started watering twice a day starting day 6. I believe I may have been overwatering, as the sprouts started to lighten in color with yellow starting to show in the middle. The edges also began to curl very slightly. I couldn’t decide whether it could be early signs of Magnesium deficiency, overwatering, or too much light, so I brought my DLI back to 13 and gave a CalMag foliar spray @ EC 800 pH 6.3 today. Any advice on how much/often to water in my 3 gallon pots at this stage would be greatly appreciated 🤘