what can a 400 watt hps harvest?

2-3 plants? 4ounce each? is that to much to expect?

a 400 watt can do some pretty impressive stuff. i just switched from CFL'S to HPS / MH. the difference is like day n night. i couldnt be any happier. but you must take into consideration EVERYTHING you do will effect a plant yeild. for example... reflecting light efficiently / medium / soil / nutrients / pot sizes / temperature / humidity / grow enviornment / stress / type of strain.... and those are just a few that will effect a plants yeild. overall tho if you take good care you should be fine. my sativa looks like shel yield anywhere from 1-2 ounces. but its also my 1st indoor medical grow... bagseed, using 2 gallon pots. soil is good but a pro mix will be better for next time

My first grow I had 6 plants in 3 gallon pots. I had some problems mostly because of miracle grow, but I still got a total of 8 ounces. This grow I have 8 plants growing in 3 gallon pots and I switched to Fox Farm OF. The plants at least have over an ounce a piece and I'm only 4 weeks into flowering. I'd be happy with two ounces per plant because I have so many growing. My next grow I'm gonna have just 4 plants, 2 midnight kush and 2 super lemon haze. I mean really it depends on how big you grow them, but if you focused on 2-3 plants I would think you could get 3-4 ounces per plant.