Leaves of seedlings turning yellowish with whitish spots


@Lornakins no worries
It should tell you how to use it for the first time some need to be conditioned if it’s factory calibrated you shouldn’t need to do anything except following mfg instructions not sure what meter your using ?
Yes you can find fox farm nutrients on Amazon
I also found them to be a cheaper on Walmart online
They offer free shipping as well on orders over 45$
Post a picture of you meter and I’ll look it up so we are in the same page
Also if you put the TDS meter in the solution you have it should read the listed ppm for your solution if it does then you know it’s accurate if not then it needs to be adjusted
You’ll still need to check ppm of run off if you experience a issue so it’s beneficial if you learn how to use it correctly I’ll try to help you if I can


Correct. Treat Coco like hydro and pH to between 5.5 and 6.1 with 5.8 being the sweet spot.


Thanks for confirming that @GrowManFitz
I’m a soil guy and I’m not familiar with coco or hydro
Only what I’ve read lol
Appreciate you jumping into the conversation bro


@GrowManFitz, and CB, Sorry I haven’t been able to get back on, as I have no internet at my house (phone line is down, DSL) and I drove 30 miles to town to get free internet.
I have adjusted the Ph water to 5.7 going in and it came out at 6.2. this was done on Monday. I haven’t done anything else, as I have been unable to get on here. I have purchased some FF fertilizer that is 5-3-1… I believe. I don’t have it with me, but I remember the N was 5 and the P and K were less. I have not used it yet because I needed your help. I don’t have the TDS meter with me, so I can’t post a picture of it yet. It is the one that came with the recommended Amazon kit that had the PH pen and the temp/humidity meter. The leaves are continuing to get worse on 2 of the girls, here are some pics taken yesterday.

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I don’t know when I will be able to get back on again, as the phone co. said by May 28th and I am a long ways from free internet, so I don’t know if I can get back on before the 28th or not.
I so much appreciate the help you guys are giving me. You all are awesome. Thank you, so much!:+1:


That’s stinks no wifi gooevthey get it fixed soon
Sounds like you got the big bloom which is great as a base Nute but you’ll want to pick up the
Grow big as well for veg
And the tiger bloom for flower
You need the extra nutrients in those two as well for a balanced diet just a FYI @Lornakins


I’m still here at this cafe, so I got your answer. :slight_smile:
Do the pics look like they need nutes, or is that PH damage?
Yeah, no internet really sucks. So for the time being, the FF that I got will do then, until I can get others. thanks, CB!


@Lornakins - It looks like a pH issue, which by default means a nutrient issue. Basically, if the pH is out of whack, the plant can’t uptake the nutrients it needs. Lower the pH going in to 5.4-5.5 and then see what the pH of the runoff is. You want the pH of the runoff to be as close to 5.8 as possible.

Also make sure you are using both Big Bloom and Grow Big. Since you are growing in Coco, make sure you get the Grow Big Hydroponic (blue label) not the green label, that is for soil.


@Countryboyjvd1971 @GrowManFitz @bob31
Yay, I finally got internet!!
I lowered the PH going in to 5.4 and with 2 of them, came out 6.3 the first time, so I did it again and it came out 5.8 with both of them. A third one, it came out at 6.4 the first time so I did it again and it came out 6.5 and then again at 6.6. I kept doing it and I could never get it to come out less than 6.4. Should I lower the PH going in some more? I just don’t know what to do.
Here is a pic of my TDS meter. It says it factory calibrated at 500 us/cm (whatever that means…?) When I put it in the solution that I pictured earlier, it read 115ppm.
I was wrong about the fertilizer I got, it was the FF Grow Big, but I didn’t know about the labels and it is the green label. I will have to order the blue label from Amazon, but it will be next week before I can get it delivered. What can I do until then? I haven’t given them anything yet. Thanks, guys!


As far as your meter does it have a x10 on it ?
And factory calibrated to 500ppm means the solution the used was 500ppm
Your fluid is at 1500 ppm so if you se 150 on meter if it has x10 you would need to multiply it by 10 and that would give you your reading with these #s it would be 1500
Take a lot and let me know otherwise I’ll need to see if I can look up meter and see specs on it
@bob31 @BIGE @Donaldj
You guys use coco don’t you ?
can you assist our friend here with the ph issue she’s having


Sounds like you have a hot medium


@Countryboyjvd1971 Yes, it blinks X10 in the lower left of the screen. Here is a picture after I put it in the solution.

@Majiktoker I don’t know what a hot medium is. I have it in coco coir. I was watering them with rainwater which had a PH of 6.4. I didn’t know until I got my PH meter that it was much too high for coco coir. This old granny is having a terrible time with my first grow. :disappointed: Seems like I am doing everything wrong. thanks for your help.


Ok so add another zero to what ever you screen says
So your ppm would be 1250 :+1:
And don’t worry @Lornakins we all have a ruff go first time out you’ll get a handle on it lol


Its alright @Lornakins, hang in there ill get you on track :slight_smile:

When you get runoff is it coming out brown or clear? If its clear there is an alkaline build up near or around root system if it is brown there is a toxic build up happening in the medium.

I noticed you ran water through with a ph of 5.4 and the run off cam out to 5.8 than 6.4 and 6.5 never going under 6.4. Take some of the medium from the bag and put it in a small dish or cup. Or even a coffee filter to get the run off and ph reading of that, that can and will help shed some light on what’s going on here

And my pleasure im happy to help


So since it reads 1250 when I put it in that Standard Reference Solution that I pictured earlier, do I need to recalibrate the little screw on it to a different reading so that I get an accurate reading when I test my water and run off? I’m confused. :confused:


Shouldn’t need to recalibrate it, if your using sink water its likely there is a mineral causing it to spike up so high


@Majiktoker aside from the pH issue @Lornakins is putting her TDS meter into 1500 calibration solution and getting readings of 1250.

I’m not sure how to calibrate the TDS Meters?


I haven’t tested any of my water yet with the TDS meter because I didn’t know what it should read when I put it in the reference solution. The reference solution is the only thing I have put the TDS meter in and it read 1250.
I have only tested the PH on my water (rainwater) and runoff after watering a plant. I have not tested the ppm on any of it yet.


Try to calibrate it one more time

Immerse the meter into the calibration solution. If the meter does not read within 2% of the calibration solution, adjust the reading by either digital calibration (for some products) or inserting a mini screwdriver (not included) into the trimmer pot (the hole on the back of the meter). Turn the trimmer clockwise to increase the reading and counterclockwise to decrease the reading.

Note that the adjuster is very sensitive. Always refere to the calibration instructions for your particular product.

@Lornakins, and @bob31


The reference solution label says:
1500 ppM (NaCI scale)
2190 ppM (442 scale)
2930 S (micro Siemens)

Which one of these do I use?
there were no calibration instructions with it. It just said it was factory calibrated at 500 us/cm and to calibrate it often.


1500 ppm NaCI scale, that should do the trick and there are calibration instructions above :slight_smile: