1st full indoor. (Accidentally erased)

You could top it now. Your at that stage where it's time to train and get hands on.

I don't believe that they are deficient. Overall, they look healthy. I'm definitely still figuring all this out myself, but it looks like it could be watering issues. Like, the dreaded overwatering or pH fluctuations. My experience has been that watering issues can quickly give the impression that there are deficiencies. I suggest drying them out almost to the point of wilting and then resume water/feed at a reduced rate. Hope this helps and happy growing!

looks like it needs N fo sure... red petioles (leaf stem) can be caused by intense led light but also could be a sign of slightly low P, too. A red streak in stem (branches / trunk - apical meristem) is potentially related to low S. ensure pH is fine.. and assumes you aren't providing some very high EC that is causing lockout -- based on pictures it doesn't seem either is the case, but you should not assume something that can be accurately measured/calculated. anyway, if it were the case you'd see a plethora of symptoms normally caused by numerous necessary molecules' concentration being too high/low and that blocks out several others from being used inside the plant, hence a smorgasborg of symptoms results

I see your feeds now of 0.5ML per Liter.. (of each of the trio) it’s good to start low but they are screaming for food now.. I’d bump that up to probably 2mL/L at least for the next feeding.

That is entirely up to you and how long you want them to be in a veg cycle. I recommend not topping. Take off the top two leaves of each branch, instead. It will free up light to get to lower branch nodes and basically do the same thing as topping without actually topping the plant. This means it will have a much shorter recovery time, if it has a recovery time at all. Some people top each branch 5+ times, so don't worry about overdoing it. If you want a thick plant, all the power is yours! Grow her how you want.

You're doing just fine, you might get some really quick growth after you flip to flower for the first 3 weeks of stretch but you can add a second scrog and continue to tuck them branches and you'll do just fine, Scroggins isn't that advanced of technique just make sure you spread to the furthest square and ya have to you might need to move it, but you're doing just fine

So ur plants are in week 13 of flower yah i would say the plant is using up the nutrients in the leaves starting to fade but having a look at one of ur pics it looks like you have mould problem happening

Both those fertilizers are NOT SUITABLE at all for cannabis. For growth you want something around 6-2-4 and for flowering something around 4-4-6 for general feeding, supplemented with some cal/mag and a P/K booster for flowering. I would say your plants are suffering from toxicity due to a nutrient salt build up in the substrate. Plain water for a week then resume feeding with proper cannabis friendly nutrients would be my suggestion. The older damaged leaves will not recover, but this should help prevent things getting much worse, although generallly, what is ahowing now in the leaves, is a reflection of what was happening in the soil two weeks ago, so things will probably get worse before they start to improve unfortunately. But getting the correct type of fertilizers for cannabis growing should be your first priority.