Battle with heat 1000w HPS

[micknearsoftpin]

Hello all - I have been reading the forms quite a bit and thanks to all who take the time to explain things. Some of you may have seen my post before about the leaves on my plants changing color. Well I solved this on my own repotting which I think fixed a ph problem I had. Well since then they are growing amazing. I have 6 dank plants of feminized church so I am happy about them. Ok with that aside let me move to my current "problem" I have a separate flower room. This room is a 4ft by 8ft by 8ft tall. It is built out of plywood inside a outdoor shed. In that I have a 1000w system that has a air-cooled hood ( two 6" inline fans running the heat out of the room with the glass cover). I also have two other sources pulling air out of the room ( I mounted window fans into the wall and sealed around them) Then I have a 5000bdu AC running on a temp control set at 80. I just ran the room for one 12 hour cycle running the light from 8 at night to 8 in the AM. The High temp on the room was 91 and the low was 81. So the AC ran all day. Humility is sitting at 51%. The effect I can see on the plants it the tops of the plants ( all in different locations as far as height from the light) have turned a very light lime green color. Also almost all of my branches ends have turned up towards the light so they must like it. This is all a test of the room and the plants in the flower room as just bag seed mids. The church is still safe in the veg room nice and cool and growing like crazy.

Ideas to get heat down - Only thing I can think of is a bigger AC or Do yall think venting air out of the shed will lower them temp inside the room thats inside the shed. It truly is a sauna outside the grow room so I would assume its a ball of heat around the room.

Question - Is the light green bad and should I bring them in ASAP back to the cool veg room?

Question - Can I grow healthy plants at 91/81 temps with good air flow?

Ok I hope all that is clear and yall can give me some advice.

micknearsoftpin Reviewed by micknearsoftpin on 08-02-2008. Battle with heat 1000w HPS Hello all - I have been reading the forms quite a bit and thanks to all who take the time to explain things. Some of you may have seen my post before about the leaves on my plants changing color. Well I solved this on my own repotting which I think fixed a ph problem I had. Well since then they are growing amazing. I have 6 dank plants of feminized church so I am happy about them. Ok with that aside let me move to my current "problem" I have a separate flower room. This room is a 4ft by 8ft by Rating: 5

[killerweed420]

You have almost the exact same sytem and conditions I have. During the summer my temp regularly gets to 90. I tried a 5200btu AC and it made my temp worse.lol Plants seem to be fine. Haven't had any hermies. I do have to keep them watered more though. I usually hit them with about a cup of water in the morning and then hitem good in the evening. Some strains will do fine with the high heat.
The other issue with the heat and humidity is mold. I have to have the fan on high 24hrs a day when I'm getting the good tight buds.

[micknearsoftpin]

Thanks for the info - What do you think the lime green change is all about? In the veg room they are under t12's 10 bulbs.

[joedirte]

usually if your taller more vigorous plants are showing yellowing (first), and your shorter plants stay dark green, then its probably nitrogen deficency. but i dont have crazy high temps like you so it could be that too.

[micknearsoftpin]

this was an instant change - its the heat or the light intensity just not sure if its bad or what? Anyone got thoughts on that? Could the heat / change in light cause a nut problem in 12 hours?

[killerweed420]

I was growing under T5's before this and I noticed the flowers turning the light green too. I think its just normal. For our size rooms a 1000w is bit overkill anyway so that could be effecting them.

[PlantHeadJ]

The 1000 is NOT overkill. 1600 watts would be 50w/sq ft. The limegreen on the top of the plant is probably from the heat. You said you went from the cool veg room to the hot bud room and 12 hours later you noticed the change right. Usually look at the newly changed things for answers. Maybe just a shock, maybe adjusting to 1000 w light after coming from T5's. Anyway I would keep an eye on them and see if the problem gets worse, I would not at this point start throwing nutes at it though. One problem at a time. If you can vent that air out of the shed that should help your temps. Also CO2 will certiantly help with those temps, not neccesssary but would help...just my 4 dollars.
Peace

[Packrat911]

The High temp on the room was 91 and the low was 81. So the AC ran all day.
Question - Is the light green bad and should I bring them in ASAP back to the cool veg room?

Question - Can I grow healthy plants at 91/81 temps with good air flow?

Ok I hope all that is clear and yall can give me some advice.

I'm certainyl not an expert, and I really can't say whether or not the lime green color is a good or bad sign, but 91 degress definitely sounds too high. Generally speaking 85 degress is about the hottest plants need to get. I'd suggest buying an extra ac unit post haste. There are a lot of other methods you can try to use to get the temps down- ice, ventilation, ac, and maybe even additional insulation to your celing and walls if you live in a hot climate.

Sometime it helps to have the actual ac unit outside of the room, with the cold air blowing air into the room through a carefully fitted tube, that way the heat generated by the ac motor wont go directy into the grow room. Air cooled or water cooled/ice cooled lights are an option too.


Just my 2 cents, like I said I'm not an expert

[stinkyattic]

I'm just seeing this now, but plants that have jsut entered flower often appear light green as they stretch rapidly for the first week or 2.
You really will need to control your temps, or add CO2 and I'd also run a silica supplement at a low dose- those two things can help your plants deal with elevated temps better, but 91 is definitely pushing it.