That's 54 sq ft space, for 18 plants, meaning 3 st ft per plant. I can fill a 2.2 st ft space with 1 plant vegging 30 days (keeping the stretch in mind), so I would say 5 to 6 weeks veg time. I have a diary here with 1 plant if you are interested
growdiaries.com/diaries/34333-going-coco-high-level-63w-100w-run-7
That been said. I hope you have enough light for that space, since you need at least 35 watts per sq ft, that means you need AT LEAST 2.000 true watts. Those invisible suns lights you have are 120 watts each and the other r2t light I've no idea. I think you should scale back the area you want to grow with to achieve that 35 watt per sq ft.