Thats just under 3-1/2 sqft, so around 16,625 Lumens optimal flowering growth
-150w puts out around 15,800L / 200w around 22,000L

I agree, One plant for its first grow.
-Try to find something to grow in that is low height, but takes up the majority of the floor.
Im thinkin youll lose 3" to 4" from the light+cooltube. Then try for maybe 5" to 6" in soil height. Optimistically 17"(+or-)1" of grow height.

Are the seeds reg. or fem.?