Quote Originally Posted by JunkYard
Thanks Racerx!

One question.. ..if I go with the 600 watt digital, I'll still need to buy a 600 watt MH converson lamp correct? You can't use a smaller lamp like a 400 in 600 watt ballast, can you?

Thanks again,


Junk~
You use just a regular MH bulb with the digital system. Not a conversion bulb. The new digital ballasts use a microproccessor that allows them to run both types of bulbs. It also includes safeguards so that if your power goes out the light wont hot start immediatly. They maximize old bulbs as well.

But like I mentioned, because of the design, the digital ballasts will degrage an MH bulb faster. If you could get 3 grows out of a magnetic powered MH bulb, then you should expect 2 with a digital ballast. I replace bulbs every single grow (every 2 grows if maybe it was a short flowering and grow time) so thats not an issue for me.

That being said, I dont use MH. There really is no reason to. If you look at the absolute best/nicest grows around here or anywhere for that matter...youll find that 75% or more use HPS the entire grow. Some people claim HPS stretches in veg. Those people are using the wrong nutrients and leaving the lights too far away. I am not disagreeing that in the veg cycle the plant would ideally like a 6000k light (white/blue) because thats what the life cycle can best utilize at that time... But after growing for a few years and being around big time growers for 6-7+ years, I have never once been shown hard evidence that MH in veg produces more/better buds in the end. I know plenty of people that have run many experiements trying to find an advantage and its always been inconclusive. MH bulbs use more power and put off more heat as well. Therefore Ive never been convinced that the hassle and cost is anywhere near worth it.

Now, T5 fluros are a whole different bag of worms. I firmly believe that T5s can be a great tool for veg. They use less power and put off more lumens (although the lumens drop off drastically as you get farther from the lamp, hence requiring you to be only inches off the canopy). They also barely put out any heat. I use T5s for cloning and for the first couple weeks of veg. When the roots are established and there is new growth, I move them under the HPS. By this time they are strong enough to handle the far more intense light output and they blow up.

Ive been experimenting with a 400 watt MH for the last couple months and I can get more plants under my 6 T5 bulbs (4 footers) with tighter growth then I can under the 400 watt MH. They also seem to root a few days sooner under the T5 and my 400MH in my small closet requires air cooling whereas the T5s just need a 150cfm squirrel cage exhausting the closet itself with a passive intake.