yellow spots. pics

[stinkyattic]

Before changing your light I would try to straighten the run of your ductwork as much as you can, and make sure that your passive intake is at LEAST as large as your exhaust; preferably a bit larger. What does your intake look like? Is it big enough, and is it low in the room?
Another think to think about is CO2. Enriching your atmosphere and running a silica supplement will allow you to run safely at temps in the high 80s with even spikes into the low 90s. However, if your humidity is quite low, you may find your plants drying out too fast.
Try to solve the heat problem with ducting first, including making sure that there are no leaks in the run from the portable a/c to its exhaust point. One thing to consider is actually moving the AC outside the room too, and setting it up to cool the air at the intake point. Something like a small tent around where your intake is, that contains the a/c and CO2 if you have it, allowing for heat generated by the a/c unit itself to escape (yup! pumps make heat!), is one approach. I run my a/c in the 'lung' area right outside my flower chamber and it kicks on at temps over 75'F. This way I am assured that air ENTERING the room never does so at high temps, and has some wiggle room to get warmer before it is exhausted.
There are as many solutions to growroom problems as there are growers. Don't be afraid to get creative. Air flows easiest in straight lines, confined to smooth ducting. Heat rises. Moist air carries a great thermal load, and exhausting it smoothly is KEY. Plants tolerate higher temps when they have ample CO2 to the leaves, O2 to the roots, and plenty of water available as long as it does not block the O2 in the root zone. Within these basic rules, you can probably arrange something that works!

[italian04]

thank you so much stink for taking the time to help me out. so i ahve vented the exhaust through the attick. the portable a/c really cant be vented anywhere else. i would rather not even use that thing if i didnt have to. i think im goin to duct the a/c vent which is right outside the room, and lead it into the grow room. if i can get my hands on a cheap 600w hps im gonna get one. i dont want high temps with my babies about to start sprouting. this is just s trial run. would love to keep the 1000w but its almost impossible to keep temps down inthe conditions i have. i have it stable at aabout 88F. 50 humid. we will see how the next week plays out. but i still have those damn yellow splotches on about 5 or 6 leaves. i dont like that. plants look healthy otherwise. and ideas? thanks so much everyone!!

[LOC NAR on probation]

If you must get a smaller light all you need is the bulb. As long as the ballast is bigger than the bulb it will run nice.

My Bro runs a conversion 400MH for veg and a 600HPS to start 12/12 then a 1000HPS a few weeks later to finish. All on a 1000 watt HPS balast. I know one guy who got in a pinch from a blown light and got a 250HPS from slows. Saved his day.

Heat is what most have to over come. Hope you get it.

Remember the bigger the light the bigger the bud.

[herbie the love bud]

italian-

Stinky is steering you straight, but I will add a little. What you have there is a phosophorous deficiency. But doubling the recipe is not necessarily the answer in your case. Do you have an EC pen? If so I would like you to check your EC daily and tell us if it is rising, falling or staying about the same. With that heat you may be transpiring too much water and your nutes may be so high they are getting locked out.

But a P deficiency is kind of rare, unless something else is going on. With that heat, have you looked at the roots lately? You might be suffering from root rot blocking any nutrient uptake.

Finally, lets try and get a cover or something on that ballast. We are taking about life threatening electrocution hazard over there.

[italian04]

ballast is out of the room. my ppm stay about the same. i am going out of town so i just changed all the buckets to ph balanced water. 2nd day of flowering. the roots are gorgeous and plus ive been using cannazym to prevent root rot and help with nutrient uptake. the yellowing has kinda slowed. when i get back i will update you guys. thanks so much and have a great stoned 4th of july!!

[polishpollack]

I've just started viewing posts on this board, but I've been growing my own for a while, and I figured I'd put in my two cents.
You write that the day temp is around 90, that's too high for an indoor grow. You've got heat stress on your leaves. Phosphorus deficiency turns leaves purple, like this, Phosphorus Deficiency

What you need to do to cool the room is get the heat from the bulb out of the room. You've got to run that six inch tubing from the other side of the reflector, the side not in the pic, out of the growspace. The fact that it's summertime is probably your biggest problem. Indoor grows need good temp control.

[italian04]

ya man i got my temp down to 82 during the day so i think i should b ok. tha plants look great. im gonna hit them with a good dose of gh nutes and bloom fert. have pics up soon

[herbie the love bud]

I've just started viewing posts on this board, but I've been growing my own for a while, and I figured I'd put in my two cents.
You write that the day temp is around 90, that's too high for an indoor grow. You've got heat stress on your leaves. Phosphorus deficiency turns leaves purple, like this, Phosphorus Deficiency

That's not a marijuana plant in the picture. Phosphorus deficit in MJ looks differently. But anyway I'm just happy he's back on track.

[polishpollack]

P def doesn't look much different. Not sure what you mean by that one, but my understanding is plant leaves, including mj turn purplish/bluish with perhaps other colors mixed in. Here's a quote from another grow site that describes the color.

"When your plants are deficient in phosphorus, this can overall reduce the size of your plants. Not enough causes slow growth and causes the plant to become weak, to little amount of Phosphorus causes slow growths in leaves that may or may not drop off. The edges all around the leaves or half of the leaves can be brownish and work its way inwards a bit causing the part of the leaves to curl up in the air a bit. Fan leaves will show dark greenish/purplish and yellowish tones along with a dullish blue color to them. Sometimes the stems can be red, along with red petioles that can happen when having a Phosphorus deficiency. This isnâ??t a sure sure sign of you having one though, but can be a sign. Some strains just show the red petioles and stems from its genes.
So pretty much the overall dark green color with a purple, red, or blue tint to the fan leaves is a good sign of a Phosphorus deficiency."

If there isn't air blowing through that silver tube, put a fan on one end and blow air across the bulb, then get the hot air out of the grow space. You can get your temp a little lower, most likely, if you try. but don't worry about it too much, as long as the plant looks good, it may not be necessary. nice plant.

[italian04]

roger that. the plants look amazing. i hade all of them in ph balanced water and cannazyme for about 4 days. (transition from 18/6-12/12) the roots BLEW up!! two of the plants i mixed with 10ml micro, grow, and blloom/gallon and a tsp of cannazym/gallon. (im using 1 1/2 gallon buckets so 3 tsp each) i just wanted to make sure that the nutes werent too much for the plant so i didnt change all the buckets. in a week i will add my awesome blossom. im still a newb and testing the waters as i go. we are about 5 days into flower. ppms were kinda high. almost 1500.