First time grow GG#4

hey Val, they're stretching because the light is too high, try dialing it in to 50cm tops, and also dimming that HID to around 250W for the first couple of weeks then increase as you see fit. This will help give those GG that GG structure we all know and love. good luck !

Topping is done usually after the 5th node, and topped to the 3rd if you are interested in main-lining/ manifold. Otherwise you can top any time after 5th node up until you start flower cycle.

All 3 answers above are spot on dude. IMO - run light feeding and don’t stress the flush time too much - strictly speaking the plants roots will only take in the nutrients it needs and once you’re good to chop the only real advantage (again, IMO as this is a somewhat contentious issue) to the flush is sucking chloro outta the leaves, arguably making for a smoother smoke (also achieved with proper curing).👍😉. Good luck to the finish.👊