I dont understand the shade cloth and are you sure youve bought the correct nutrients. I had canna vega A+B but it was for a recycling hydro setup where PH sould be about 5.5 and is no good for a plant in soil. Water your plants and check run off colour to decide wether to flush. Red stems is excessive phosphours so a wild guess (without more information) you need to flush and stop feeding. Check youve got the right nutes and ideally whether youre 18/6 or 12/12 you need full sun amd complete darkness so the shade needs to go. Personally i dont feed when the plants are that young as they are very sensitive but ultimately will keep on growing. Buy a moisture meter as the cannabis plant likes to compltely dry out before being drenched with water/feed.
d0ct0r