2nd Grow *Rootbound Help*

k so my first grow was garbage .... bought everything i needed for a cheap grow .. and germinated a few seeds .. worked ... but i was way too impatient ... so in the end it didnt work ... well now its been 3 weeks since i germinated/ planted two seeds i got from this weed that had it all in it .. if you can understand that ... basically when i got a nug of weed. .. and started to bust it ... seeds would be wrapped in weed and fall out once busted .... so i got a few pics and i need to know .. should i change what im growing them in ... i know i shouldnt have them in clear cups cause last time i did that people on here said not to ... but ive done it .. and it worked up till now and is still goin good ... but the roots have hit the bottom and some are even starting to curl .... they are basically clear plastic drink containers ... (1 water and one pop i believe ) so there like 5 maybe 6 inches in height or depth how ever you look at it ... should i change to a bigger pots now and if so i need basic steps on doing it ... i dont wanna stress the plan .... so should i do it well its light out and like ... i guess fill a pot with dirt/soil then somehow put it in without the soil crumbling and the roots/plant getting ruined ?? help is crucial and much appreciated

The first pic is of my setup



Then the next 5 are of 1 plant that has the roots growin helllla which make me think i should transplant











Then these last two are of my second plant

get bigger pots bigger the better

Yeah, dont use anything smaller than a two liter bottle, and even those get root bounded pretty fast.

But from the looks of it, you're still ok for now, but I'd transplant ASAP.

ok so i transplanted the one that had the roots comin down like crazy ..... but the soil i used was moist .... is this gonna be fine .... basically what i did was cut the bottom of the bottle and then put it in place of the hole in the pot .. and held the dirt down while lifting the bottle .... it worked perfect .. im pretty sure i didnt stress the plant .... anyway is the moist soil bad or good ? should i spray lighter with nutrients until the soil starts to dry up ?

makesure the roots cant be exposed to lights. didyoutransplant intoasolid bucket? should put a pic of your plants up more help will come

i jus took those pics today .... yes there solid buckets .... black ... i know the roots shouldnt be exposed to light but it seemed to work for the first 3 weeks and still goin on 1 plant