400 watt mh in a 5x5 tent??????

Now i will be using a 1k light but was wondering if you can veg with a 400 and flower with the 1k. Is it a smart idea to veg with a 400 in a 5x5 or is that a waste of time? Just trying to save money on my electric bill.
Thanks.

they will take longer to veg under a 400 so you probably wouldn't save anything

Well, you have to look at actual cost vs. time. It depends on what your current KWPH charge is in your area, but where I am in Metro Atlanta, it's 11.6 cents. That said, here's how the cost would break down assuming your run an 18/6 schedule:

1000 watts: 1000/1000 * 18 * 30 * 11.6 = $62.64 per month.
400 watts: 400/1000 * 18 * 30 * 11.6 = $25.06 per month.

So, you're looking at a savings of roughly 60%.

So let's assume you'd veg for 6 weeks on the 1000. That would come to $93.96 total power cost.

Now lets assume you'd have to veg for 8 weeks on the 400 to equal it out. That would come to $50.12 total power cost.

So, even if you wound up vegging a couple of weeks longer on the 400 to make up the difference, you'd still save damn near 50%.

You may be able to run your lights at night or off peak hours and save a little $$ on your bill.

I think when wanting to do things economically fluorescent lights are the clear winner, T5 High Output being the best I've used for speed. You don't get the growth rate you do with high intensity lights, but you are able to spread the light out for your small plants using a fraction of the electricity. As a bonus a slow grown plant is more mature, has thicker stems especially if you bend them weekly by hand, and for me they yield better. If you switch to fluorescent veg don't forget to keep your 1000w flower light back an extra foot for the first week so the plant can adjust to high intensity. After 1 week go ahead and move the light to your normal level. You can avoid this if you are able to allow an 1-2 hours of sunlight on them before flowering for a week, or you can ignore this if they have received some sunlight their whole lives.

Thanks guys for all your input and I apologize for the late response. I'll be running a 1000watt my here in the next week I'll have to invest in some t5s cause those 1000 watt light get expensive but I'll just have to do it for this grow next grow I'll put up som t5s and recommendations for the type and wattage I'll need?

I was using a 600 for each veg and flower... now use both for flower. I went with a 4' 4 bulb t5 light for veg. Got it off amazon for like $75ish and it pulls around 275 watts. Not the same rate of growth, but its been sufficient. I need another one to really cover the area I want to, though.

400w mh will work in a 4x4 but it is under-kill. 600w would fit a 4x4 more realistically. If you havent got CFLs yet and you want good results AND to save on electricity, check out CMH or ceramic metal halide bulb technology. They run 315 watts and have bulbs different than your classic metal halide. They also have special ballasts. You will require a special setup but you'll get good results. For veg go for the 4200K bulb to veg. They produce little heat too but output similar to a 600w mh. It sounds like snake oil but they really are amazing. I imagine they will replace CFLs in the next 5 years being more efficient, better results, and covering a large area. A 315w cmh (only wattage made, no 400, 600, or 1000w variety available) will cover a 4x4 area. Have a read, see what you think. Good luck.

Also, going 400w to 1000w could be stressful in my opinion. I'd start flower off at 600 then go to 1000 after a week so you're not blasting them with such a huge amount more of light than they're used to. Even if they take it, you could be looking at a huge stretch which may not be beneficial. Same practice if you sided with a CMH. They sell the phantom CMH kit on amazon for around $400, thats your bulb, ballast, and reflector, so almost plug and play. Phantom CMH kits are pretty good setups and can be used for flower too, a 3100K bulb is made for that with more red frequency in it.

Other than the Sun, COB leds are the most efficient grow lights on the planet! With a 400watt hps and fans I was pulling 527 watts from the wall.. now I'm pulling 268 and my tent is much cooler...

use the 400 for 2 to 4 weeks

then use the 1k set on 600 for a week or 2

then use it full blast a week before flipping or a week after