Need some help

[tryingtolearn]

OK I'm having some problems just not sure what to do?I'm growing in a ebb&flow table with hydroton,my plants seem to be missing something or are they burning up? This is my second attempt at growing this way,the first time went great no spots on leaves great yield now this. I'm using GH 3 part per instructions on bottles 1-2-3 in flower and my leaves are turning yellow on the ends and eventually they will be all yellow
ph-5.7
ppm 970 (.05) cal
res. temp 70
What am i missing this time around?

 

[Guest]

Looks like light burn. How much lighting, how far away from plants, and what are temps?

 

[tryingtolearn]

I'm using 2x600 hps about 18 inches above the plant tops,(4X8 table)the room gets up to about 78 deg toward the end of the light cycle

 

[Space Ghost]

I'm stumped! it could be a very finicky strain, you could try bumping up the ph a couple points...

 

[Blackvelvet]

I think they are burning. You might want to tinker with watering frequency. As the hydroton dries out, the water with ferts becomes more concentrated. If that does not work, maybe reduce strength. You can always add more to correct a deficiency but not much you can do for a plant that is burned.

 

[Guest]

Hey Trying!

Lemme take a stab.

First off you didnt say if these were lower leaves, upper ones, new growth, etc. It really does matter.

Second, I would be shocked if this was light burn. I have ONLY seen that with 1000w running inches from a plant (guy got a rock'n cooling system for the air so he was able to get em too close). However, ya never know. The telltale sign that this is light burn is it would be on the top leaves, closest to the light.

Here's what I think without any more info: I think these are lower leaves and they are not right below your light (based on you saying that eventually they would all be yellow). I think your plant is eating them up because they are not getting as much light as the upper growth. When I've grown multiple sativa's in limited space, they would grow into each other and end up blocking some of the light below. This caused the same effect for those leaves - yellow/brown/dead.

Nothing to worry about unless I totally missed it all in which case I'd ask for a plant shot so we can see em while they're still on there....

 

[Berry_Coughin']

I have burnt plants with a 26 watt cfl and it does look very much like light burn to me...

that's my stab at it.... light burn.....

 

[Guest]

Ohhhhhh! My bad Berry - I thought 'light burn' was caused by the light being too intense for the plant. To burn a plant with a cfl it would have to be right next to the leaf and would then burn it literally as in heat. I was talking about the bleaching due to intensity - my bad.

 

[tryingtolearn]

thanks for all the replies,its not just the lower leaves that are turning
i was watering every three hours but have just changed to four times a day,three times during the light cycle and once in the dark-trying to keep the ph from going up to much before i can catch it(have had the ph swing to 6.5 a couple of times)
i don't think its light burn,i just don't know
would ph lockout cause this?

 

[MTF-Sandman]

What's your water source and PPM/PH before nutes? Kinda looks like a sodium issue locking out K...

 

[tryingtolearn]

water is from the tap,seems pretty good though ppm around 40-50 and a ph of about 7.5-7.8

 

[Guest]

Here's another thought and one I run into a lot.

Let's say 3 weeks ago I had a pH swing that I missed for a few days, causing lockout in the plant. So I quickly fix it and everything seems a-ok.

Today, I'll walk in there, see the brown leaves and wonder what is going wrong now. What I forget is once a leaf burns, it will not regenerate. Therefore it's possible, unless these are affecting new growth, that you are seeing results from the past when you had your pH swing.

I always try to take a step back and think about what actually causes leafs to burn like that. Nute lockout, high temps, lack of light, insects.

Deduction says if you remove each one of those variables then the issue will be solved. I personally have a tendency to over complicate things, which normally ends in worse issues and frustration.

Good Luck!