Possible PH, heat stress, or mite problem; can't tell

[weatherboxes]

I have a few things going on. First is there are small white dots on some of my newer leaves and the second is that some of the larger fan leaves are curling up slightly on the edges and down on the tips.
I will be testing my water & run off PH today with strips and update that as soon as possible.

SOIL:

How long has this problem been going on?
Started about 1 week ago

What STRAIN are you growing?
Jedi Mind Trick (Indica dom hybrid)

What was the establishing technique? (seed or clone?)
clone

What is the age of your plants?
3 weeks

How long have they been in the soil mixture they are in now?
2 weeks 3 days

Were they in the same mixture when they were seedlings/smaller
plant? If not, what mixture were they in before?
No, they were in rock wool

How Tall are the plants?
over 1 ft (just LST'd)

What PHASE (seedling, vegetative or flower) are the plants in?
vegetative

What Technique are you using? (SOG, SCROG etc)
LST

What size pots are you using? (Include how many subjects to pot)
1 plant/5 gallon pot

What substrate/medium are you using? What brand of soil mixture are you using?(percentage of perlite, vermiculite...etc?)
Fox Farms Ocean Forest w/ 1 tbsp dolomite lime

What brand Nutrient's are you using?
Fox farms grow big, big bloom, tiger bloom

How much of each nutrient are you using with how much water?
*Knowing the brand is very helpful*
1tsp grow big, 2 tsp big bloom to 1g allon of water

How often are you feeding?
1 x week


What order are you mixing your nutrients? (example: veg nutes 1st, bloom 2nd act)
Grow big then big bloom

What is the TDS/EC/PPM of your nutrients used?
What is the pH of the "RUN-OFF"?
How often are you testing pH/ppm/EC/TDS?
What method of pH test was administered? Using Strips? pH pen?
Using strips once I get them today

How often are you watering?
Every 3-4 days

When was your last feeding and how often are you feeding?
4 days ago 1 x per week

What size bulb are you using?
400w

How old is your bulbs?
brand new

What is the distance to the canopy?
16-20inches right now it is closer to 20"

What is your RH Factor? (Relative Humidity)
54%

What is the canopy temperature?
82 F

What is the Day/Night Temp? (Include fluctuation range)
Day Low 80's / Night mid to low 70's

What is the current Air Flow? (cfm etc.)
4 inch can fan and two small fans

Tell us about your ventilation, intake exhaust and when its running and not running ?
Can fan pulls heat from the bulb/hood out the top of the box. 1 fan is inside the box in between the plants & another is outside of the box blowing air in through the doors which are remaining open to regulate heat.


Is the fan blowing directly at plants?
A little

Is the grow substrate constantly wet or moist?
No

Is your water HARD or SOFT?
IDK

What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water?
Filtered water from the fridge

If using tap water, what is the ppm/EC/TDS of the water right out of the tap?(Only if you have a tds pen)

If using RO,Distilled,mineral water, what is the ppm/EC/TDS without any additives?(Only if you have a tds pen)

Are you using water from a water softener?
No

Has plant been recently pruned, cloned or pinched?
LST'd two days ago

Have any pest chemicals been used? If so what and when?
No

Are plant's infected with pest's?
Not to my knowledge

 

[weatherboxes]

Using an API freshwater test I determined the PH of my water directly from the filter is approximately 7.4-7.6 or lower.
The PH of my runoff is approximately 6.8.

I don't know how accurate this test is. I am using 5ml test tubes with drops of PH test solution and a color range to determine the PH.

 

[weatherboxes]

I used my small microscope to rule out mites. I couldn't see any on the damaged/curled leaves. That only leaves possible heat stress? The box isn't excessively hot but I moved my lamp up a few inches nevertheless.

I still can't figure out the small white spots on some of the leaves.

Anyone have any idea's? Thanks.

 

[intotheunknown]

Spray them with anything?
Hard to tell from the pictures, but are these spots discoloration, or are they necrotic?

 

[RonSmooth]

If I add Fox Farms Tiger Bloom to my (soft) tap water, it drops the pH into the low 5's or high 4's.

That is way too acidic for cannabis.

Then you water them with filtered water that is too alkaline.

The pH is out of range and that is causing problems with nutrient uptake. Treat the pH issue before you try to treat anything else.

Stop using filtered water. Most tap water contains minerals which plants need. Nutrients are often lacking in essential trace minerals. Tap water makes up for what the nutrients lack.

The lime you added to the soil is also affecting the pH. While it may help buffer somewhat, it is a much better idea to just get the water in proper pH range. The Ca from lime and organic sources like oyster shells runs out over time. While Ocean Forrest is amended, IME it is not enough to sustain plants through flower.

Why did you add the lime to the soil in the first place?

Get a good pH/EC meter. Know the proper pH range for cannabis in soil. Get your nutrients/water in that range. Give that to your plants. Monitor for a week and see if you notice improvement.

And stop measuring runoff. It only adds confusion and unnecessary panic.

 

[Siomha]

just had the same problem. but my white spots were worse than yours.
the ph was off. it was too high. there were black flies also, I finally got rid off.
the ph is 6.0-6.2 now and the plants are green and healthy as can be.
good luck

 

[Siomha]

i forgot to mention. I bought osmosis filters, they work wonders. and added some mag/cal. they recovered within no time

 

[stihgnobevoli]

based only on what the leaves are telling me, i'd say you have a touch of too much food, and it might be a little hot or rather dry. i think if you drop the feeding down a little bit or get it cooler it will go away. all in all theres nothing to worry about right now.

Is the fan blowing directly at plants?
A little

this is prolly your main issue

 

[weatherboxes]

just had the same problem. but my white spots were worse than yours.
the ph was off. it was too high. there were black flies also, I finally got rid off.
the ph is 6.0-6.2 now and the plants are green and healthy as can be.
good luck

If I add Fox Farms Tiger Bloom to my (soft) tap water, it drops the pH into the low 5's or high 4's.

That is way too acidic for cannabis.

Then you water them with filtered water that is too alkaline.

The pH is out of range and that is causing problems with nutrient uptake. Treat the pH issue before you try to treat anything else.

Stop using filtered water. Most tap water contains minerals which plants need. Nutrients are often lacking in essential trace minerals. Tap water makes up for what the nutrients lack.

The lime you added to the soil is also affecting the pH. While it may help buffer somewhat, it is a much better idea to just get the water in proper pH range. The Ca from lime and organic sources like oyster shells runs out over time. While Ocean Forrest is amended, IME it is not enough to sustain plants through flower.

Why did you add the lime to the soil in the first place?

Get a good pH/EC meter. Know the proper pH range for cannabis in soil. Get your nutrients/water in that range. Give that to your plants. Monitor for a week and see if you notice improvement.

And stop measuring runoff. It only adds confusion and unnecessary panic.

I add lime to the soil as a PH buffer. It's something I did in previous grows with no negative effects. I never had PH issues with previous grows but I was not using the same nutes. I want my PH around 6.8. I know Im too alkaline with the filtered water for sure.

I moved the fans to get them off the plants entirely.

Im wondering if anyone here can recommend a good PH meter? The one at my hydro store is about 40 dollars and only for PH and is not waterproof. They also recommended a 180 dollar meter that measure PH/EC/PPM.

 

[Siomha]

I have a ppm measure and I dont like it at all. Never use it for this reason.

Just use simple pm stripes, they do it for me every time. Never had pm issues with it.

It is kind of difficult to get the water right with filtered water. Some guys at the grow store recommend the osmosis filter for the plants and it seems it is worth the money. They were never so green and nice like they are now. The only cost like 120 Euro here and you can use the filter for a long time. After all the plants turn out to look great like never before without any problem so far.

 

[secretstoner420]

Hey guys sorry to invade the thread im new to the forums site and havent worked out how to start a thread yet.. i have sone issues of yellowing veins and curling leaves on 10 day old seedlings roughly around 2 or 3 inches tall i originally thought it was overwatering as soil was very moist im using plant magic supreme and only watering with 7.0 ph water with a 1/4 does of cal mag im usually an outdoor grower but switched this year am using an 800mm2 by 1.6m high tent black orchid and a 300w mars hydro led panel and a 75 watt cfl the led was very close roughly 6 to 12 inches from tops of seedlings im now assuming its either light or heat stress and have moved lights higher transplanted from small pots into 3 gal pots the strains are auto amnesia haze auto critical rapido and wipeout express auto from heavy weight seeds.. anyone got an idea on what it possibly could be i dont have many fans either to add that in but the filter and outlet fan are on all the time..

 

[secretstoner420]

Heres a few pics

 

[TedNugget]

Im wondering if anyone here can recommend a good PH meter? The one at my hydro store is about 40 dollars and only for PH and is not waterproof. They also recommended a 180 dollar meter that measure PH/EC/PPM.

I would highly recommend the "Accurate pH 4" ph meter (model cw495)

Here is a link to it (I didn't buy it from this site though) - http://www.horticulturesource.com/accurate-ph-4-p16190

It works great and the actual pH probe is detachable and can be replaced (for like $20 I think) if the bulb ever goes bad, instead of having to replace the entire meter.
It stay really well dialed in too. It's very easy to adjust the set-screw if it does get out of range, but I hardly ever have to adjust mine.
I've had numerous different ph meters and this has been my favorite for sure. It's right around $70 but well worth the money.

 

[Four20omky]

Too much Fert, thats for how many gallons of solution your feeding your plants.. your "MATURE" plants.. those are not mature plants.. those are young.. anything under 2 feet is pretty small, even with a wide root system it can only use so much.

NOT TO MENTION, actually.. yes.. TO MENTION: Fox farms soil, doesn't suck. it has LOTS of fert in it.

I'd stop feeding them till they start showing "deficiencies" , or at least for a little bit.
Just water them with water that isn't nuclear... and you should be good... for now.