courtesy of skunkushhybrid ^^^^ here's a good co2 method http://www.rollitup.org/view.php?pg=...article&id=286

but for lights it doesn't get any better than HID's. there's two basic HID's, MH (metal halide) and HPS (high pressure sodium). ideally you'd want both. MH is a primarily blue spectrum light which is better for vegging and HPS is a primarily red spectrum light which is better for flowering. the reason for that is because the plants can use the light more efficiently in their respective stages of life. However you can use just one of those light all the way through and still get a really good yield. If you do decide to get just one of them get a HPS. If you're like most indoor growers you'll be spending more time in flowering than vegging so the HPS will be more effective.

Based on comments above, what do you guys think about this chart (see link below)? It appears to me that if you drop below 5.5, you're going to start to lock out nitrogen and definitely lock out phosphorus and magnesium?? (To be clear, I'm a relative newb though and trying to learn all I can from you guys, the maestros!)

http://www.gardenscure.com/420/attac...ient_chart.gif

Yo D wanna split this? It's a nice lamp.
I say go 50-50

NEW 400 watt HPS Grow Light 400w Hydroponic Sodium Lamp - (eBay item 180178296114 end time Nov-18-07 19:00:00 PST)

i have pictures coming soon to show you guys our set-up. But we have a problem now and the plant leaves are turning yellow. I got pH meters and the pH was extremely high this morning so we got pH decreaser and jsut put it in. Anyone have an idea how to cure these plants quick??

How old is that chart? I have read something different very recently. I did say, new evidence to suggest... although my plants are quite happy even up to 6.0 in coc coir...

Its definatly a nitrogen problem right? so are we lacking nutrients or what?

D this is a good investment...
NEW 400 watt HPS Grow Light 400w Hydroponic Sodium Lamp - (eBay item 180178296114 end time Nov-18-07 19:00:00 PST)

Quick ref chart for Nutrient deficiencies in Hydro - 420 Magazine

I need help quick. My plant is truning yellow but not dying yet. And the new leaves are coming as if the plant is completely healthy. How ever the first set of leaves is getting yellower every day but no signs of dying. I fixed my pH problem and lowered the level and i havent seen any improvement. Anyone have any solutions i can try

Hey skunk, I have a question for you, I was always under the impression that when you flower you want to bring the pH up to uptake P and K better, is this wrong?

I've never come across that before... and the science behind correct ph levels and optimum uptake of nutrients has not been clearly defined, so I couldn't say for sure. Unless I took a degree maybe, and got myself a lab. lol.

I'd say though that plants will uptake nutrients at a specific level of ph, and that there should be no need to change this during flower...

Is there any evidence of changes in acidity levels of soil during the bloom period in an outdoor grow with nature doing all the work?