Low ph run off and brown spots. in coco/perlite.

I am in week 6 of flower on the strain EEEEE by Mass Medical Strain and I noticed the other some of the top leaves had brown spots on them. I upped the calmag to 5ml per gallon but the next day it looked like it had spread or gotten worse. I tested the run off and the ppms are ok but the ph is too low. I'm in a coco perlite mix and I feed 4 times a day. I have been having trouble keeping the drip running to run off. It keeps just saturating it but not running off and i have to mess with it.

I've been feeding it Advanced Nutrients Sensi Coco Bloom A+B, silica, Big Bud, calmag, Realgrowers Recharge. A total of 1,300-1,400 EC. Because it looked like it had gotten worse I tried to flush it last night with just water+recharge in between a feeding. Lights haven't come on yet to see how they look.

Anyone know what might be causing this or how I can fix it?

What's your pH at run off? With little to no runoff you could be seeing lockout. Flush by hand an option?

BaginsZA said:

What's your pH at run off? With little to no runoff you could be seeing lockout. Flush by hand an option?

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Run off pH is at 5. Yeah it's in a 3 gallon smart pot and I gave it about 2 and a half liters of water+recharge inbetween feeding yesterday. I can't tell if it helped or not though. Also I am using a 240w QB and a 300w mars blurple in a 2x4. Forgot to mention that.

Do you mean 1300 ppm? Too high, make it 900.
5 ph too low, make it 6.

As mentioned ph should be around 6ish. Feed lower ec and make sure you get plenty of runoff. Repeat. Get the runoff ec lower.

Too low or too high ph and elements do not get absorbed.

Thanks I lowered it down to 900 hopefully that helps. The nutrients are supposed to be ph perfect and are ok going in but maybe no runoff or too high of ppms led to lock out or something and made the ph run off low?

I also noticed tonight there is a bunch of gnats around the top of the coco! I'm going to pick up some mosquito dunks tomorrow. I read those should work and maybe some diatomaceous earth or yellow sticky tapes.

stckyprp said:

mosquito dunks

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Crush them up and sprinkle over top of coco. Top feeding distributes the gnat killing bacteria into the pot.

You can also Float them in your res.

Sticky traps for flyers.

stckyprp said:

Run off pH is at 5. Yeah it's in a 3 gallon smart pot and I gave it about 2 and a half liters of water+recharge inbetween feeding yesterday. I can't tell if it helped or not though. Also I am using a 240w QB and a 300w mars blurple in a 2x4. Forgot to mention that.

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Did you get plenty of runoff with the 2.5 L? I use 5 gal fabric pots and need a couple of gallons to really get the salts out if I suspect lockout in mid-flower. With coco I add at least some cal-mg when doing a mid-grow "flush". I pour about 5L in, wait 15 minutes then pour another 3L. Maybe try 6L or so for 3 gal pots. Kill those gnats too, the larvae is eating the roots and not helping. Vacuum out the runoff water too, don't let your pots sit in it for long.