Bulb 6in from top, signs of heat stress

[angelicious]

Folks, as the title says, my girls are showing signs of heat stress even though the bulb is 6 inches from the top leaves. The top leaves are slightly tacoing, but the serated edges are folding back in on themselves.

I have a small closet grow, 2 x Nirvana Bubblelicious autos under a 300w dual spec CFL and reflector. Mylar sheeting, bio bloom light soil and nutes, (Grow, Bloom, Alg-a-mic).

The bulb itself is quite hot for a CFL, I can touch it but only for a second. Most CFLs you can hold in your hand, even the higher wattage ones. The temps in the closet are kept between 24 & 27oC using an 6inch oscillating fan and leaving the closet door open. I don't have an exhaust fan, nor am I in the position to get one at present.

I know I should raise the bulb to get the heat away but I'm afraid if I raise it any higher the girls will lose light. Has anyone else had a similar problem? If so, how did you resolve it? Cheers!

 

[Evil-Mobo]

The only thing you can do is control the heat or back off the light trust me I can show you pics of my sunburned plants from a UV bulb that was too close for comfort.

I ended up ditching the bulb and now my T5 setup runs cooler and can be a lot closer to the plants.

 

[angelicious]

Yeah I'd say I might have to ditch the bulb eventually but for now I have to stick with it, budget constraints don't allow for further purchase. Balls anyway.

I've moved it to 9 inches above now, temp is still about 26oC, leaves are still taco-ing but I'll give them to adjust. I have a 6inch fan on high speed pushing the hot air away from the them. I don't know what else to do...

BTW thanks for taking the time to reply, really appreciate it.

 

[Evil-Mobo]

Yeah I'd say I might have to ditch the bulb eventually but for now I have to stick with it, budget constraints don't allow for further purchase. Balls anyway.

I've moved it to 9 inches above now, temp is still about 26oC, leaves are still taco-ing but I'll give them to adjust. I have a 6inch fan on high speed pushing the hot air away from the them. I don't know what else to do...

BTW thanks for taking the time to reply, really appreciate it.

See what happens because sometimes you can get away with warmer temps if you have good airflow. Is there a fan circulating air in the area?

 

[angelicious]

I have a 6inch fan in there at an angle so it's blowing hot air away from the girls, yet still there's enough of a breeze to rustle their feathers. Now they're still vegging, and have started to flower so at least they're progressing, but most of the leaves are still taco-ing. Temp is still 26oC

 

[Gregor Eisenhorn]

It's going to be a pain in the ass with those temps, but nothing too serious. I had 30C for almost all of my flowering period and apart from some insanse stretching, tacoing and airy buds, nthing bad happened.

 

[angelicious]

Oh that's good to know, thank you! Stretching is definitely not a problem though, they're a short bushy plant anyway and I had a few hiccups at the start that stunted their growth, so monsters they definitely won't be! Here's hoping they turn out nicely.
Thanks again!

 

[Roobarb]

Can you post a pic? Are you certain of those temps? Seems unlikely - your bulb is already too far away. I wired up a bathroom extraction fan on a wardrobe grow once. Worked a treat and cost €15

 

[angelicious]

I have 2 mercury thermometers, they both say the same. In fact I moved things around slightly this morning and it increased the temp! Hmmm...

 

[Evil-Mobo]

Oh that's not bad at all. You caught it early. Would it be too much trouble for you to get a second fan? I would get a second fan facing the opposite direction and mounted a little higher and see if that helps to circulate the air and blow the heat up.

You have an intake? Even if passive? Air needs to move through there........

 

[Rusher]

I have 2 mercury thermometers, they both say the same. In fact I moved things around slightly this morning and it increased the temp! Hmmm...

+1 for thermometer shaped like a little bear.

 

[angelicious]

I wired up a bathroom extraction fan on a wardrobe grow once. Worked a treat and cost €15

Details or GTFO
I know I should look at an extractor fan but I live in a rental and the wardrobe is my landlord's, so I'm not keen to cut into it. A tent is a future purchase when I have the money so I can set things up properly then, for now I have to use what I got...

Oh that's not bad at all. You caught it early. Would it be too much trouble for you to get a second fan? I would get a second fan facing the opposite direction and mounted a little higher and see if that helps to circulate the air and blow the heat up.

You have an intake? Even if passive? Air needs to move through there........

Not enough room for a second fan unfortunately, unless I put it above the reflector, but that seems pointless to me as the air from the new fan wouldn't be able to circulate downwards - it's a tight squeeze in there, the reflector width is almost that of the wardrobe itself.

There is air moving around, I keep the wardrobe door open so the air is getting blown over the plants and out the opening. Temps in general outdoors are down too so that's dropped things by a degree or 2. Happy days! We're in pre-flower too, this morning I got the subtlest hint of the beloved smell. Mmmm.....

+1 for thermometer shaped like a little bear.

It was left over after my daughter outgrew her baby bath, waste not want not I say!