I just bought a 430watt Son Agro HPS and did the calcs to find out the LUX and its around 29,000 lux, is this gonna be enough? whats the max amount of plants i can grow in about 4'x5' with that amount of light.
That light isn't enough for that big of an area. The light could do about 1/2 of that area. Your goal is 50 watts per sq. ft. with a HID. that area is 20 sq.ft.
The most amount of plants would be done as a SOG (Sea of Green). At 1 plant per sq. ft. So with that light you could do about 10 plants but that would be pushing it.