I would like to know what kind of nutes you are using... next, i would go with a feed/water/water schedule. if you are using built soil (fox farm, miracle grow, roots organic) you already have nutes in your soil for about 3-4 weeks. If at any time you start seeing funny colored runoff, hold on a feeding until you have watered them two more times. it is easy to turn soil toxic with too much watered into it, esp if you are using cheap (poorly built, not inexpensive) nutes. if this is your first time, i would recommend dialing everythg back to no more than half strength of what directions tell you. nute companies are really good at telling you to use more than you need so they can sell you more bottles with different ratios of NPK in them. in soil, i personally use a weak dilution of age old grow, age old kelp for foliar spray, and xtreme gardening mykos WP as an innoculent. i have never torched a plant in soil, and I have had well above average yields any time i grow in soil. it helps that you shared you are growing under a 1k, but are you venting it or just letting it vent itself? 4 degrees in your garden can mean much more evaporation, hence more frequent feedings. it will also help you a ton with watering and feeding schedules if you have a hygrometer to measure humidity in your garden. when you flip them to bloom, (assuming they are photo period phenos), you will want to discontinue a grow formula of nutes, and switch to a bloom formula (something with a LITTLE N still in it to keep photosynthesis healthy through bloom. The last couple of weeks, you are best to just give them pure water with maybe a tiny bit of bud enhancer (bud candy, bat guano sweet leaf, MOAB, etc. These will force the plant to begin to cannibalize itself from the bottom up toward the flowers, and make sure that all available plant energy is focused on growing bud, not stem or leaf. I know this was long winded, but I hope it does help get you a bit more comfy with nutes on your new girls. best of luck