First time outdoor auto grow, north uk

So this is my first attempt at any outdoor grow or growing auto flowers, so will be interesting to see the results, especially with the nice weather we’re getting during lockdown. BCN XXL & Amnesia were the first two i germinated and planted, but after relocating the plants in my garden i realised i had space for 2 more, hence the Tangerine & Purple. The Tangerine broke soil 4 days after the original two, the purple punch took longer to germinate and was only planted on day 6, so this one will be a week behind the rest once it pops. Obviously no nutes added yet, just been feeding with water from my heavily stocked fish tank, so far i’m happy with the results considering it’s been just about a week. The XXL has really spread it leaves out wide, standing at about half an inch tall. The amnesia has taken a taller approach, standing at just over an inch but with less broad leaves. My garden gets great sunlight during the day, hitting the plants at around 8am and going down around 7:30pm. It looks like the weather will be turning rainy for the next week or so, so i will be transferring the planting into a makeshift grow box inside until the weather perks up, hopefully will have no negative effects but we’ll soon see! 🤞🏻 Question for anyone who has temporarily moved outdoors plants inside, should i try and mimic the light schedule they’ve received outside? or would a 20/4 schedule be safe for them, to try and get as much growth as possible while they’re indoors? thanks in advance!

So week two i started feeding the plants low amounts of blackstrap mollases mixed in with their water, i think the first feed i went a little overboard with the molasses so there’s a couple brown spots on one of the plants, but nothing that looks too concerning. After dropping the amounts, they’ve all seem to have shot up a fair bit. They’ve been inside this week under a CFL bulb due to poor outdoor weather, but now the suns back they’re back outside! Never grown autos before so i’m not too sure what the growth rate is like, are these looking like a decent size for 14 days? thanks! also the purple punch struggled to break soil and didn’t seem to be surviving well, so i decided to get rid so i can focus more on the other 3.

About halfway through week three now, not seeing much height growth but definitely noticeable gain to the leaves, all of them are starting there next lot of branches. The XXL is the biggest out of the three but that doesn’t surprise me, the clues in the name 😂 Decided to throw some BioBizz Bio-Grow in the mix, only to find out that it’s 100% molasses which is what i’ve been feeding it anyway, fed at a 50/50 mix of each hasn’t done any harm, and they definitely shot up a bit after feeding! Did some research on the small spots i was getting on one plant and seen that it might be a magnesium/sulfur/calcium deficiency and heard that small amount of Epsom Salts can help. Added 2tsp to my water and can see the affects already! One question, ive noticed the XXL has developed a deep purple stem (see photos) is this something i should be concerned about? It’s clearly not affecting her growth, hoping it’ll mean some purple buds are coming my way! 🤞🏻