Weird size of plants. Same age

So hrowing in coco coir 70/30 perlite grow dots and worm castings. Planted 4 2 died 1 left is fast buds gorilla cookie auto and 1 is royal queen seeds royal gorilla auto(dont know what ones what) they are both about 9 weeks old. Just changed lighting to 18 and 6. Used cal mag. I have bloom booster. I have snapped 5 branches on the tall 1 saved 2. The other is only 28cm hight. Theres such a difference and i dont know why. Also the ph is 6 +/-0.2 humidity is 40% average and temp 25 Celsius average. Can anybody give me soom advice on whatvto do or look for know im in flowering? Take about 2l water wcery second day. Second week in proper flower where the white pistils where really noticable. Any tips or help guys firat grow.

Plants vary some big some not so much especially when they aren’t the same strain. They can vary by feet. In the same strain you can still see different sizes depending on genotype and phenotype.

Yeah think indica is tsll and wide and a sativa is short and bush(or other way round) but i hink because thry were hybrids with the same % of strain type i thought maybe they might be roughly the same shape and size. But i had a few problems in first week i killed 2 royal cookies auto and nearly the small one with nutrients. Im suprised it survived. Iv made mistakes but just happy to have that experience. Can anyone see any potential threats or things to look out for in such a crucial time. I seen 1 solitary little black fly today in the tent but as i looked it was impossible to see again…?

Sativa is tall and indica is bushy. As of now they look to be doing alright. I wouldn’t say there is any abnormal potential of anything going wrong just stay the course

Thanks bro ats the boost i needee. Ao juat keep plowing on. Great thjbf ti gear tha ks bud at was a confisence boost