This happened a few hours after using grow booster,what is it?

hi i used grow booster for the 3d time yesterday,i started with 2.5ml per 10l the first time 5ml the 2nd and 10ml yesterday.i water once using nutrients and then 2 times using just ph water.
can you please expain what the problem is and what to do to resolve it?

also i would like to know if i must remove some yellow leaves from the bottom of some plants which are there from a former problem i had or if i just leave them be until they fall by themselves

I would suggest filling out a support ticket, which has a link in the Beginner Section.

Without knowing a lot of the factors, I would think it would be hard to tell by just pictures.

Things Iknow about deficiencies, which are basic are : yellow leaves on old growth could be lack of nitrogen, yellow on new growth could be lack of iron, brown spots, where the veins remain green could be lack of calcium or magnesium…

I think the folks with the experience would like the info given in a support ticket, which will help them suggest possible problems.

Yes that support ticket would really help. It could be a few things ph, nute burn come to mind first.
COPY/PASTE: This “Support Ticket” into your forum post.
Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so = NA

Strain; Type, Bag seed, or NA

Soil in pots, Hydroponic, or Coco?

System type?

PH of runoff or solution in reservoir?

What is strength of nutrient mix? EC, or TDS

Indoor or Outdoor

Light system, size?

Temps; Day, Night

Humidity; Day, Night

Ventilation system; Yes, No, Size

AC, Humidifier, De-humidifier,

Co2; Yes, N

Add anything else you feel would help us give you a most informed answer. Feel free to elaborate, but short, to the point questions and facts will help us help you smile

We had a previous Support Ticket posted, but lost it during the “database issuer” @MacGyverStoner @latewood. Can help better

Strain; Type, master kush

Soil in pots

PH of runoff or solution in reservoir?6.5

What is strength of nutrient mix?i use grow booster from ilgm


Light system HPS 600

Temps; Day, Night 23-18

Humidity; Day, Night 55-80

Ventilation system; Yes

Co2 no but i grow in room that gets a lot of fresh air 24/7

my problems started on week 3 when i noticed that the bottom leaves were turning yellow,i guess the soil i used didn t have enough nutrients for so long.
then i started marijuana booster on week 4 using 2.5ml per 10litres but 4 out of 10 plants got burned leaves the day after.
i am not satisfied with the overall growth of my plants i am in week 6 of vegging and most of my plants are about 30-40cm.
i was advised to measure the run off at that time but this is something i can t do,don t know how and every video i watched got me confused so i don t know the exact number of ppm.
plants are not growing more than 1-2 cm per day and i don t know what to do.i have no money to invest on anything else right now so if there is something i can do to make them grow faster i am open to all responsible suggestions cause i don t want to see another effort to grow going to waste.already tried 3 more times but all failed due to lack of equipment at that time.
and what makes me really sad is that now i have invested a lot more money and doing everything by the book i may have even more problems than before…so guys please help me
thank you

6.5 is the pH of what? You didn’t say anything about how long between feeding, it seems almost as if you are way over feeding it, but you gave no time schedule.

What videos?

Yes, you need to learn how to measure the run-off, it isn’t that hard, you just measure the run-off that comes out the bottom of the container. You should get a TDS meter pen, as well as a way to measure pH like strips, drops, or also a digital pH pen.

Also, are you over watering?

Fresh air 24/7? How does this work, where is the “fresh air” coming from?


Check out Robert’s video on you tube and his blog from this site

Robert’s youtube on testing soil:

Robert’s blog on testing soil:


And have you seen this:

Tip of the leave curve up

Wow, it’s amazing, I got lucky and found a video that covers exactly what you asked about testing the run-off, and then he talks about heat.

Check it out:

Then some other guy talking about just testing pH in the run-off as well. I agree, pH in the run-off can be a little lower than what you put in without it being a problem, but it is best not to let it it get too far out of range.


Thanks Mac great info.

i have my grow tent inside a room which has a small window right behind an opening that the grow tent has,i keep the window open during the day and keep it closed only for the 6 hour dark period.
i have 2 circulation fans inside the tent and a carbon filter.
i water one time with nutrients and then 2 times without.
i checked the videos you posted but i have a small problem.i water each plant with 1l of water but there is no water running off the container (there are 4 holes in the bottom of every container).should i use more water than 1l?maybe i am overwatering as mac G said but i am sure that i wait until the soil is almost completely dry before i put some water in
i also have ph and tds meters.
i am thinking of bying this
and i would like your opinion,if it is going to help or measures even how dry the container is and if the plant needs watering or not.

Yes, you need to water until some comes out the bottom. Watering should normally be done this way, to full saturation – the entire container, and then don’t water again until totally dried out.

I hear a lot of people just not seem to be happy with soil probes accuracy, I’d trust measuring the run-off more, also that meter will only show pH, moisture, temp and light. And what you really need to know is soil fertility, or nutrient concentration building up in your soil, and this meter doesn’t check for that. Learn to test the run-off, it isn’t that difficult and it sounds like you already have the tools.

Check out this link here where I go into a lot of detail about testing the run-off and watering to saturation and not watering again until very light and almost totally dried out:
Yellow spots on a few leaves of one plant, one leaf on other, none on third - deficiency?


i tested the run-off to 5 of my plants and the results are:
container 1) 6.6 ph – 1910 ppm
container 2) 7.1 – 1840
container 3) 6.9 – 1300
container 4) 6.7 – 1480
container 5) 6.7 – 1440

I’m guessing the ones with the highest run-off ppm or pH farthest from 6.5 are the ones with the damaged leaves?

actually those 5 are the least damaged,i will test the other 5 tomorrow morning and let you know.
what should i do if ph or ppm are too high?
i checked the video you posted and this guy says that the ph of the run-off to all of his plants is about 5.5 and ppm should be 1800 the most if i understood correctly.

I don’t think your soil is mostly coco coir, and so it should be more at 6.5pH for soil, 5.8 for hydro.

Normally with many nutrient lines a ppm of 1800 in the 0.70 conversion is ok, it is an EC of 2.5 to 2.6 and is what he is probably talking about. The 0.5 PPM conversion would only be about 1250.

However, a PPM of 1800 in the 0.5 conversion would be like 3.4 EC, and would be too high with most nutrient systems.


so you re saying that ppm in my containers is too high?i really have a problem understanding all the things you said above so please forgive my stupidity for asking again.
and if they are too high what should i do?
and still haven t figured out the reason why my plants are still too short and what to do to fix this.they will be 2 months old at 11 of november and the tallest of them all is 48 cm,but most of my plants are around 30-40cm.
if you could please give me some advise of how to fix this with simple words i would really appreciate it,
i am a guy who has started to love growing weed but i have never planted anything before,so my knowledge about growing plants in general is extremely poor

Yes, very likely it is too high, both pH and PPM.

and what does it need to be done to fix this?
is this the reason for their slow growth?

It is very likely part, if not the main cause of your problems.

You need to bring the pH to 6.5, and probably flush, or only water with pH adjusted water to get the ppms down.

so i stop nutrients until i get the ppms at what numbers?
and how will i lower the ph?i am watering with 6.5 should i water with a lower ph to something like 6.0?

You might need to flush your soil in the ones that have the worst problems and worst ppms and/or pH.

You would flush with low or zero ppm water to lower your ppms, ppm and pH recommendations are in the nutrient schedule.

Yes, you would need to water with a lower pH to adjust your pH down. I went into detail about how to understand your pH readout numbers in the link above I gave you. Keep in mind his numbers are for coco, you have soil, as I said your pH should be at 6.5