Possible N Deficiency ? 600w MH/HPS tent grow

cc08150 said:

That's whats up keep us informed as to how they do. You may try misting the leaves with water when the lights are off or when they are raised really far away....don't do it while the lights are close. But this helps to get rid of some excess nitrogen in the leaves. What is your temperature and humidity; I can't believe it's page 2 and I haven't even asked.

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I think ill have to look into misting the plants when it's their bedtime !!
Would it be smart to use Liquid Gold by ram ridge as a foliage spray or just use phd water !
I haven't got an exact reading of the temp n humidity but I know my soil temp at the top of each pot is around 29-33C !
My guess would be jus over the plants it might be a little higher or even a little lower as I got 2 oscillating fans right on my plants n a 6inch exhaust sucking out all the hot air n venting it straight out the window !
I will get a temp/humidity reader within the next couple of days and give you the exact readings mate !
I know the temp n humidity is important but couldn't find any readers at local shops so I bought what I could until I make a trip down to the hydro shop !

Also I raised my lights an extra 20cm just incase I was burning them!

I'd just use plain water as long as it's between 6-7ph you should be fine without having to ph it...if you ph it you run into the problem of having sediment on the leaves from whatever agent you used to lower/higher the pH. I've never personally foliar sprayed or fed, but plain water is what you want, you're def not trying to add any nutes.

Ok we have found your problem if you got over 33C temps at soil level, they are gonna be much higher at plant top level since the light radiates heat even with fans blowing. So do you have an air intake anywhere or just sucking air out? Best growing results are gonna be seen if you can somehow get your temperature down to 22-27C

cc08150 said:

I'd just use plain water as long as it's between 6-7ph you should be fine without having to ph it...if you ph it you run into the problem of having sediment on the leaves from whatever agent you used to lower/higher the pH. I've never personally foliar sprayed or fed, but plain water is what you want, you're def not trying to add any nutes.

Ok we have found your problem if you got over 33C temps at soil level, they are gonna be much higher at plant top level since the light radiates heat even with fans blowing. So do you have an air intake anywhere or just sucking air out? Best growing results are gonna be seen if you can somehow get your temperature down to 22-27C

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Water out of my tap is at ~7.0 sometimes a little lower sometimes a little higher, yeah ill forget about the liquid gold she dont need more nutes lol!
So heat stress you think mate ?
I have no got an intake I only have an exhaust and 2 oscilating fans ! The exhaust is vented straight outside to reduce heat in the room the tent is in !
Also doesn't help that we are in summer and there isn't an air con in that room !
Ill get in contact with my hydro guy and get an intake fan in their !
i managed to drop the temps a lot last night by venting the heat straight outside instead of jus vventing out of the tent!
The temps I've had from transplant till yesterday where a lot higher more in the 40c range ! So I've managed to drop them down to around 30-33 during the day and at night I'm guessing would be more like 26-30!
Also I have my light schedule to start at 6pm n finish at 12pm so the lights are off during the hottest parts of the day and only on late afternoon through the night ! Trying to keep temps down as much as possible now

So the exhaust fan is just for hot air in the room itself to be evacuated? Yea you need to find an inline fan to cool your 600watt light. If it is in an air coolable reflector that is....and yea, do your lights on cycle at night time so it is cooler. I'm thinking that heat coupled with maybe too much initial fertilizer stunted the root growth of the plants. I've seen pictures in my grow book that look similar

cc08150 said:

So the exhaust fan is just for hot air in the room itself to be evacuated? Yea you need to find an inline fan to cool your 600watt light. If it is in an air coolable reflector that is....and yea, do your lights on cycle at night time so it is cooler. I'm thinking that heat coupled with maybe too much initial fertilizer stunted the root growth of the plants. I've seen pictures in my grow book that look similar

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Yeah I have an inline exhaust fan sucking out air from inside the tent and I have 6inch ducting going to the window to duct the hot air outside instead of into the room the tent is in !
This alone has made a significant improvement with heat but I will need more !
is there a quick fix way to reduce heat until I get my intake fan ? Or just hope for the best that the hottest summer days have past and its only gonna get cooler!!

Make your exhaust fan a intake fan

topfuel29 said:

Make your exhaust fan a intake fan

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and then just use a box fan as an exhaust if you really have to lol. Or exhaust it into the rest of the house....you said you don't have AC in that room but what about the rest of the house...?

cc08150 said:

and then just use a box fan as an exhaust if you really have to lol. Or exhaust it into the rest of the house....you said you don't have AC in that room but what about the rest of the house...?

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I only have air con in the main lounge room lol ! No way am I putting the tent in their for every Tom dick n Harry to see lol
If I use my exhaust fan as an intake how do I exhaust the hot air in the tent ?

Sorry guys but what's a box fan lol !

I do have a very very large inline exhaust fan with active carbon filter but it was used in a really large grow room with like 12 x 1000w HIDs!
If I somehow manage to fit a 5ft inline exhaust fan into my tent it will suck the tent in on itself lol !

Figured out what a box fan is lol !

Ok what u lads think of this idea !

Im gonna buy a cheap stand alone air con!
Ill run some 6inch ducting from the air con into a port of the tent as an intake !
So instead of jus normal temp air coming in it will be a lot cooler and ill still have an exhaust fan to remove heat !

jezzystylez said:

I only have air con in the main lounge room lol ! No way am I putting the tent in their for every Tom dick n Harry to see lol
If I use my exhaust fan as an intake how do I exhaust the hot air in the tent ?

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Run the exhaust back out the window. Make your exhaust fan a intake fan ( before or after the tent). Run the exhaust back out the window. Make it a closed system. That's if the air outside is cooler than the air inside the house.

topfuel29 said:

Run the exhaust back out the window. Make your exhaust fan a intake fan ( before or after the tent). Run the exhaust back out the window. Make it a closed system. That's if the air outside is cooler than the air inside the house.

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My only issue with running an intake fan with outside air is that it's summer over here which means day temps are around 35-40C and night temps are like 25-30C !
Thats why I thought of using a portable air con as the intake and leave my exhaust to pull hot air !!
But since I haven't got a portable ac as of yet so ill try your idea of the closed system and see if that helps drop temps

jezzystylez said:

My only issue with running an intake fan with outside air is that it's summer over here which means day temps are around 35-40C and night temps are like 25-30C !
Thats why I thought of using a portable air con as the intake and leave my exhaust to pull hot air !!
But since I haven't got a portable ac as of yet so ill try your idea of the closed system and see if that helps drop temps

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Are you running your lights at night, when its cooler?

If you just run a 6" line from your portable (stand up) A/C unit to your tent, the A/C will have to be running all the time that the lights are on because obviously the AC thermostat will be reading the room temperature, not the actual tent temperature. I got a stand up AC unit that i put in the corner inside my 55" x 55" tent when it gets too hot....takes up about the space of one plant, but its in the dark corner of my tent, so doesnt really take up usable grow space. If you got the AC inside the tent, it will cycle on and off as needed and not run your bill sky high...

cc08150 said:

If you just run a 6" line from your portable (stand up) A/C unit to your tent, the A/C will have to be running all the time that the lights are on because obviously the AC thermostat will be reading the room temperature, not the actual tent temperature. I got a stand up AC unit that i put in the corner inside my 55" x 55" tent when it gets too hot....takes up about the space of one plant, but its in the dark corner of my tent, so doesnt really take up usable grow space. If you got the AC inside the tent, it will cycle on and off as needed and not run your bill sky high...

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Yeah that actually makes a lot more sense instead of ducting it into the tent run the portable ac in the tent so it can work of the actual heat inside the tent instead of outside room temp !!
so much quality info guys thanks heaps

My lights are run during the late afternoon hours through the night !
Lights are off during the hottest parts of the day from 12pm-6pm !!