...tho the pix are a little hard to see.. how big are the plants, and are they already in three or five gallon buckets?

Your existing lighting should be ok for the first couple/three weeks, but you'll probably have to add way more to get thru the veg. cycle, and then a bit more for flowering.

T5 high-output have a good lumens/watt ratio, and some CFL bulbs get close to Metal Halide numbers, but you should prolly pick up a couple more 54w T5s to help thru veg, then switch to a 400 or 600w HPS for flowering, if budget permits.

Make sure your ambient air temp is no higher than 78-83f, and the ph going in is 6 to 6.3, and you should be fine. You have good soil and nutes there, and if the plants are from good stock, you could (should!) see a good harvest.