When should i flower?

and do you think i could change the time up? its only at like 15 1/2 hrs light. could i gradually bring that up or no?

Depending on the phenotype of the plant, you will need to veg until 24 inches tall to get close to the output you want, but you must have the lights to do that too. You will need a 1000 Watt setup to get that kind of production off one plant, but it can be done.

Dude, go out and get some good nutes...personally I like ff...ur plants r gonna need P and K during flower if u want to get the results u r looking for...mg alone is not gonna cut it