I keep my 600’s in glass enclosed air cooled hoods (blockbusters) and plants stress closer than 18” with tons of ventilation and circulation fans.

If i ran 1000’s i would need 2.5-3ft easy above the canopy.

got pics?

MIMedGrower said:

I keep my 600’s in glass enclosed air cooled hoods (blockbusters) and plants stress closer than 18” with tons of ventilation and circulation fans.

If i ran 1000’s i would need 2.5-3ft easy above the canopy.

got pics?

Click to expand...

I’ll post some updated pics later but this was a few weeks ago from a previous thread I started.


Yesterday I backed them down to 750W to see how they take to the light and they seem to be a little happier. The glass covered g-hoods I have are cool to the touch because I have my exhaust running through them in series and they’re all the way up to the top of my tent. So now I’m not sure what others issues it could be. I watch so many videos and forums of people running 1000s in tents with no issues once you have cooled hoods so I’m honestly a loss for words with the lightening.

Ok i scanned the thread.

The acid you used may be building up in the pot. Or you may not be feeding enough. Dont know why you are focused on cal mag. Its just a supplement to be used as needed. Base nutes should be the focus.

I would use a grow ratio nute about 1.4 ec for the big plants. And i would feed every time until i see they have had enough.

And i think its a nutrient issue not light. The spectrum degrades when dimmed so if you can keep them at 1000 watts its better for the plants.

what is your humidity? Sounds like a Ca transport issue. I see this quite a bit in my 2k aircooled rooms when the plants stretch a little too much and im in the 2ft circle directly under the bulbs. Room temps might be in check but the leaf surfaces might be getting warm. This is with magnum xxxl's with a 12in vortex running 2 rooms. Shit tons of airflow along with a/c. Just cant be helped so I keep plant height in check since i have 90in ceilings. You have to know your strains and get a methodical approach to veg timing, clone taking, and topping.

I should say my room temps don't ever creep over 76 in the summer at canopy level. ANother reason I hate doing seed runs not of clones and usually run those in my tent under the 630's.

My rel humidity has been anywhere from 55-65%. I live on a tropical island so humidity is no issue here lol. As recommended MlMedGrower I started upping the nutrients to see how much they can handle. The acid I was using all along was phosphoric acid so that issue has been resolved. I was mistaken to believe it was hydrochloric. I fed them at 900ppm with base nutrients flora nova grow and bloom With a little calmag and some silica to bulk up the weaker branches since it’s their second week of flower...the runoff was 650ppm so they were quite hungry. Waited two days then gave them floralicious plus with some kelp, great white mycorrhizae, molasses and calmag at around 500ppm. The runoff was 600. Then waited two days and gave them straight water, molasses and a little calmag again to bring back some green to the canopy. The ppl of the watering was 450ppm and they’re all now sitting with a runoff of 600ppm. At this rate they’re consuming about 200ppm a day worth of food so I should be able to give them another proper feeding of base nutrients in a couple days.
Any recommendations for my feeding schedule? I originally had an organic day for my second day of feeding that consisted of banana tea, recharge powder, great white myco, kelp, molasses and some coconut water but I cut out the organic day until I get the girls back in a happy shade of green. Uploaded a video below after defoliating a bit last night and having backed down the lights to 750w for two days. Please leave all remarks guys...Don’t spare feelings...I’m a big boy...just care for maximum health and output for my girls

Looks good. Keep doing what you are doing until the leaves tell you otherwise.

I use a 1000w HPS bulb and have plants about 2 ft away but have no problems, but I think you might be having issues with the focal point of your reflectors. When mounted horizontally in a reflector hood, nearly all of the energy is directed downward instead of being distributed evenly in all directions. It is feasible that the focus of the reflector could be too strong directly under the hood.

Jimster said:

I use a 1000w HPS bulb and have plants about 2 ft away but have no problems, but I think you might be having issues with the focal point of your reflectors. When mounted horizontally in a reflector hood, nearly all of the energy is directed downward instead of being distributed evenly in all directions. It is feasible that the focus of the reflector could be too strong directly under the hood.

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Thanks for your input bud. I was thinking that as a possibility as well. These bulbs actually screw in vertically and not horizontally but regardless I do this the focus is intensified on the hood because of how it’s made ...will take a video on startup when lights on starts later

Jimster said:

I use a 1000w HPS bulb and have plants about 2 ft away but have no problems, but I think you might be having issues with the focal point of your reflectors. When mounted horizontally in a reflector hood, nearly all of the energy is directed downward instead of being distributed evenly in all directions. It is feasible that the focus of the reflector could be too strong directly under the hood.

Click to expand...

Hey bro...here’s a video of my lights starting up and a view of what the bulb looks like in the hood. Let me know if you think it’s an issue.

tringrow said:

Hey bro...here’s a video of my lights starting up and a view of what the bulb looks like in the hood. Let me know if you think it’s an issue.

Click to expand...

My light is alsoo mounted vertically, but I use a white reflector instead of a shiny metal one... that eliminates any hot spots that can happen. My bulb uses a round reflector that hangs above about 2/3 of the bulb, leaving the bottom /3 of the bulb giving light off of the sides with only a smaller percentage being directed downward. This really helps with side development and I get some tall sativas indoors. In your setup, nearly all of the light is directed downward. If you were getting hot spots, I would expect to see variations in the leaves that are on the same plant but different areas.

Jimster said:

My light is alsoo mounted vertically, but I use a white reflector instead of a shiny metal one... that eliminates any hot spots that can happen. My bulb uses a round reflector that hangs above about 2/3 of the bulb, leaving the bottom /3 of the bulb giving light off of the sides with only a smaller percentage being directed downward. This really helps with side development and I get some tall sativas indoors. In your setup, nearly all of the light is directed downward. If you were getting hot spots, I would expect to see variations in the leaves that are on the same plant but different areas.

Click to expand...

That’s exactly what’s happening. Any ideas as to what I should do to rectify this issue before I get too far into flower and run into more issues as they stretch further? Maybe getting a horizontal mounted hood instead of vertical? I’d rather spend a little to save the harvest rather than proceed with something that could end up scorched and sub par

Jimster said:

My light is alsoo mounted vertically, but I use a white reflector instead of a shiny metal one... that eliminates any hot spots that can happen. My bulb uses a round reflector that hangs above about 2/3 of the bulb, leaving the bottom /3 of the bulb giving light off of the sides with only a smaller percentage being directed downward. This really helps with side development and I get some tall sativas indoors. In your setup, nearly all of the light is directed downward. If you were getting hot spots, I would expect to see variations in the leaves that are on the same plant but different areas.

Click to expand...

These are some of the leaves from one plant. Bigger leaf is the top of the canopy.

I believe I have solved the issue! The hoods were the culprit the entire time. These g-hoods are meant to be hung in rooms that have a 9-10ft ceiling and not in a tent. It’s way too intense and the throw of lumens from the bulb is way too focused and high. I went to the store today and bit the bullet...bought two new hoods and now I can safely say that I feel fully dialed in to my environment. It’s crazy cuz I was getting a serious hue of yellow off of the last hoods and now I’m getting more of a closer to white hue...which is what I’ve been aiming for all along. I thought it was my bulbs or something tbh. With today’s change I can now run my lights at 1000w, these hoods are better at keeping temps low so I’m now sitting comfortably at 74deg, and the color of my light in the tent has changed which has been a pet peeve of mine all along. So happy I finally figured this out. Thanks to everyone who helped give some input!! Thanks to Jimster, MlMedGrower and cemchris!!! Wish you guys all the best moving forward with your grows as well!