just startin out

k im postin this thread to try to get a lil help from some experienced growers ive had two trials and errors but none made it all the way to harvest so i need some help so i got a 100 watt hps a 3 1/2x7 foot cabinet with a shelf in the middle the hps is mounted on the bottom half i may add some t5s to the sides of the cabinet and i got a week old seedling in some soil with pearlite and vermiculite im thinking about just ditching the soil and use just the pearlite and vermiculite ive heard that works well for nutrients i got the three part gh micro, bloom, and grow and superthrive and some gh compost tea not sure if thats all i need but it seemed legit im not to sure on how the ph levels work either i havnt started using them yet tho it just popped outa the soil when should i start using them and how much should i mix in the water? and id like to obtain some more seeds i was wonderin what would be a legit place to get these? thank u for ur time