4 week flower browning tips

[ToFarGone]

So I’m on day 28 of flower. Starting week 4. Everything has been going smoothly. Temps and RH are in check. Flowering under a 600w HPS. Plants are in 6” rockwool with a top drip system. Using maxibloom staying close to 600ppm plus or minus a bit. Ph I dose down to 5.9 then let it creep up to 6.2 then dose down again.

So I just noticed some browning on the edges of my leafs. Any guesses as to what it is?

 

[inDC4now]

Hello @ToFarGone -- has anything changed reacently? Light closer to plant? Fan closer to plant? When is the last time you calibrated your pH pen?? Maybe peek at the waste water pH and ppm and compare?

 

[ToFarGone]

I just calibrated my pen. Nothing’s changed in the grow room over the last few weeks. I know the ph is good

 

[rkymtnman]

nute burn. if i had to guess your RW is saturated with salts and the actual ppm is way more than 600.

 

[Wastei]

So I’m on day 28 of flower. Starting week 4. Everything has been going smoothly. Temps and RH are in check. Flowering under a 600w HPS. Plants are in 6” rockwool with a top drip system. Using maxibloom staying close to 600ppm plus or minus a bit. Ph I dose down to 5.9 then let it creep up to 6.2 then dose down again.

So I just noticed some browning on the edges of my leafs. Any guesses as to what it is?

View attachment 4423647

I guess your running hydro on flood tables? If that's the case how often do you change rez? EC and pH will tell you a lot but it's very hard to calculate organic waste matter, enzymes etc that the plant produces.

Do you do weekly rez change?

If you run rockwool you must flush the medium in mid flower to prevent salt buildup.

 

[ToFarGone]

nute burn. if i had to guess your RW is saturated with salts and the actual ppm is way more than 600.

I read to never flush rockwool? I was too dripping 3 times a day for about 20% runoff each time the runoff gets recycled into the res and I do water change every 2 weeks.

I added another drip cycle to flush it a bit more

 

[hellmutt bones]

Yeha dilute the res a bit or just do a quick res flush and recalibrate with new res.

 

[ToFarGone]

I’ll try knocking the ppm back to 500 then

 

[rkymtnman]

I read to never flush rockwool? I was too dripping 3 times a day for about 20% runoff each time the runoff gets recycled into the res and I do water change every 2 weeks.

I added another drip cycle to flush it a bit more

i put RW in the same category of medium as coco. it needs to be flushed out occasionally.
in coco you flush with very light nutes, never plain water.
in RW, i would do the same IMO> some others that grow in it might chime in with different method to flush it.

 

[rkymtnman]

I’ll try knocking the ppm back to 500 then

more like 150 to 200. measure your runoff too to see what it's at.

 

[ToFarGone]

So I set the res at 200 and started a flush with the top drippers. First runoff came out at 760ppm so obviously there was a build up. I kept flushing until what I put in I more or less got out. They are mature plants for can’t overwater them in rockwool.

I added 1 more feed now up to 5 feeds a day. and upped the time for each feed by a few minutes in hops to just push more runoff each feed and avoid the salt buildup.

Any suggestions on a ppm for straight maxi bloom going forward?

 

[rob333]

So I’m on day 28 of flower. Starting week 4. Everything has been going smoothly. Temps and RH are in check. Flowering under a 600w HPS. Plants are in 6” rockwool with a top drip system. Using maxibloom staying close to 600ppm plus or minus a bit. Ph I dose down to 5.9 then let it creep up to 6.2 then dose down again.

So I just noticed some browning on the edges of my leafs. Any guesses as to what it is?

View attachment 4423647

mild nute burn keep going she will push thru it trust me

 

[rkymtnman]

Any suggestions on a ppm for straight maxi bloom going forward?

i think 600 is pretty good for bloom. just think about adding the same flush you just did maybe every 2 weeks/3weeks into your routine.

 

[ToFarGone]

i think 600 is pretty good for bloom. just think about adding the same flush you just did maybe every 2 weeks/3weeks into your routine.

Much appreciate the advice. I’ll leave it at 600ppm then

Would you still flush at the much lower ppm or can I just flush at the higher ppm to remove excess salts ?

Still Learning rockwool. Hardest part was getting them rooted in the 6” cubes. Once I had decent roots it’s been impossible to overwater with the drip system

 

[rkymtnman]

yes

flush at the much lower ppm

 

[ToFarGone]

yes

So I got a better pic of the leafs today. Appears to be affecting mostly the top of the plant. I should also add it’s straight maxibloom and nothing else. I am also using RO water with no cal mag?

 

[rkymtnman]

So I got a better pic of the leafs today. Appears to be affecting mostly the top of the plant. I should also add it’s straight maxibloom and nothing else. I am also using RO water with no cal mag?

i see maybe a touch of Mg deficiency in that new pic. maybe add some Epsom to your res.

are your roots OK? any rot possibly ??

 

[rkymtnman]

could also be a Ca defic too. hard to tell if it's rust spots or just nute burn.

maybe cut your maxibloom down a bit and run cal/mg to get you back to that same 600ish ppm

 

[ToFarGone]

i see maybe a touch of Mg deficiency in that new pic. maybe add some Epsom to your res.

are your roots OK? any rot possibly ??

Roots nice and white that I can say for sure.

So my comes out of the RO at 20.

How much cal/mag would you run? Maybe

Base 20
Calmag 130
Maxibloom 450

For a total of 600?

 

[rkymtnman]

Roots nice and white that I can say for sure.

So my comes out of the RO at 20.

How much cal/mag would you run? Maybe

Base 20
Calmag 130
Maxibloom 450

For a total of 600?

i would run full dose of cal/mg and then see how much maxi you need to add to get to 600.
are you using calimagic by GH? that's my preferred cal/mg if i ever need it. i'm on well so got plenty of Ca and just add Mg via Epsom