Dying leaves (starting from tips)

[Tw1sted]

Strain: Big bud XXL
I'm growing flood/drain in clay pebbles. Floods 4 times/day
Currently at about week 8 of flowering.

Loads of leaves are turning brown and dying, mostly right under the lights.
I'm using 4 x 180watt LED lights over a scrog of two plants. It's a lot of light, probably double what I need. The lights cover the canopy.

Current food is Ionic Bloom and Ionic Boost. I add some Cal/Mag too.
My TDS was around 3000 but I brought it down to 2500 now 2000 in case this is nute burn. (that figure is after everything measured in the res)
PH is between 5.5 - 6.5.

Temperature swings from about 15C at dark to 35C when lights on.

I've looked at pictures online of different illnesses but I've drawn a blank.
The sticky thread in this forum has broken images so that's no real help.

Please help!

 

[hotrodharley]

Nute burn deluxe.

 

[Extrome]

35C (95F), no wonder your leaves are cooking. 15C (59F) is fine for night temps, but problem is it's a huge difference from daytime temps, and you really want to have only a 5 to 10 degree difference from day to night. What are you using for ventilation and what's it's CFM rating? How big is your grow area?

First thing to do though is lower your day temps at least 5 degrees Celsius. Either raise your lights or turn some off.

 

[Extrome]

Nute burn deluxe.

That too now that I see the extra shininess and color . But 95F is a little high

 

[Tw1sted]

Great suggestions thanks guys!
The tds peaked at 3500 a few weeks back as I wasn't keeping an eye on them. Seems the dosage on the bottle is way too high, but my critical kush used to love it!

Yes the temp is high. My fan has a 'high' mode which will bring it right down. I didn't turn it up as my heater wouldn't make much different if we have a particularly cold night. Didn't want to risk colder night times but I'll do it now.

Harvest in a couple of weeks or so anyway so I may as well stop the nutes altogether soon.

Thanks again!

 

[*BUDS]

Dont stop the nutes, with hydro you feed right up till harvest or the final weight will be affected. Looks like nute burn and 95 is far too hot, better cold temps than hot in flowering.

 

[rkymtnman]

your EC was at 3 and now it's 2?

i'd give a 24hr flush and start back with light nutes.
don't starve them when they are putting on the most bud weight.