Do these leaves have some kind of burn on them?

Bottom leaves tend to always bring up problems, maybe suggestively get a Nutrient tracker and make sure you giving the plants the nutrients it needs, too little is often much better as too much. Especially in its early stages of veg as the plants has its own nutrients. Many people get it wrong when they think they should give nutrients in the beginning. It's in my opinion not needed at all other than water and maybe a Nitrogen solution would be best. Once your plant is in its 2nd month then Nutrients are very important as long as they are regulated as again the plant doesn't need alot of nutrients, may only need Nitrogen and Magnesium Sulphate (Epsom Salt). But from there this should provide you with a better crop whilst in Veg. Good luck

I saw you using voodoo juice, but I didn't see anything about any other nutrients. If all you are giving them is voodoo juice, they may be hungry.