Questions about runoff ppm

Hello this is my first grow. It’s indoor white widow autoflower. I’m using FFOF and my run off is 1600 ppm is this to high they are in flowering stage and about a month old. My ph run off is 6.4. Any help would be appreciated

No, 1600 in flower is good, in fact you could even take it up to 2000 in mid flower.

you can see recommended ppm here.

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Thx I didn’t know what the chart ppm meant. I thought that what it was suppose to be going in thx agian

At 1600 you definetly dont need to feed agian
Just ph water till the ppm comes down then youll know they are uptakiing the nutrients
You can bring it up a little bit if you wanted to

Ill generally feed in the 1800 range when feeding in flower

Follow mixing schedule for given week is great but i don’t recommend you feed wvery other watering as schedule recommends
Watch the ppm of you run of and let it drop before feeding again



Hey thx, another question what number should look for to feed again.

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Start geed when you see the numbers drop below 1000 i feed full nutrients and need to feed once a week just keep a eye on the run off and once you getvthe feel youll know when to feed watch it he girls they will let you know sometime ill water three time before i feed other times ill feed after one watering all depends on the plant even plants of the same strain can have different needs as farvas nutrients ive had plants that love nutrients and other that don’t any
In time youll be able to read the plants I promise it get easier lol



Hope this helps

Start with 600 PPm for week 1
900 PPm for week 2
1200 PPm for week 3
if you go over 3 weeks veg
1500 PPM week 4
1800 PPM week 5 and hold there
at bloom I flush and go to 1000 PPM week1
1300 ppm week 2
1600 PPM week 3
1900 PPM week 4
flush weekly…VERY IMPOTANT
and hold there until last 2 weeks and ad your bloom enhancers.



This is large but I think you should have this. Copy and paste it to your files

Knowing What Your Plants Are Eating and How Much They Can Handle
October 20, 2016 by Devin Martinez
One big question growers ask is “Why are my plants suffering even though
I used all the right nutrients, feeding cycles, lighting cycles, and adjusted
temperatures and conditions to their absolute best?”
That’s because their pH and PPM levels are off, making it difficult for your
plants to eat. pH refers to potential of Hydrogen ions in your water, which
will determine if your water is too acidic or has too much alkaline in it.
PPM (parts per million) refers to the concentration of minerals and soluble
matter in your watering solution.
Correct pH and PPM levels are the backbone of any grow, and will be the
difference between a healthy grow and a huge waste of time and money.
pH Levels
Simply put: the right pH level will create an environment where your plants
can absorb nutrients quickly and easily, leading to a better harvest.
Nutrient-rich water is filled with elements that are helpful to your plants.
However, if those elements can be broken down properly those same elements
can harm your plants.
pH levels is important to understand because the right level will determine
the quality of helpful bacteria in your water that help break down elements,
helping the metabolic rate of your plants. How? In two ways:?

When pH levels are too low (pH level of around 5 of lower), heavy
metals like iron and aluminum change and can become toxic to your plants ?

If the pH level is too high (pH level of around 6.5 or higher)
elements like calcium and phosphorus can’t be broken down completely, which
will hinder the growth of your plants
This change in properties is due to how acidic your water is or is not.
You’ll want your plants’ nutrients to be a little acidic otherwise they can’t
break down, but too much acidity and your nutrients can become toxic.
So remember: pH too low= toxic to your plants, too high= growth decrease.
That’s why you want to have the perfect level of acidity in your water,
which will be around 5.5-6.0
Typical pH Levels ?

3.5 and below: Root Damage ?

4.0-4.5: Poor Nutrient Uptake ?

5.0-5.4: Good pH Level ?

5.4-5.8: Perfect pH Level ?

6.0-7.0: Acceptable pH Balance ?

7.5-8.0: Poor Nutrient Uptake ?

8.5 and Above: Root Damage

Note: Soil grown plants tend to need a little bit higher of a pH than hydroponics
because soil retains and releases certain elements to your plants at different times.
However, both hydroponic and soil pH levels should stay within the same optimal range
of 5.5-6.0 pH.
PPM Levels
PPM (Parts Per Million) refers to concentration of the particulates in your feeding
From minerals found in tap water to natural elements found in your nutrients, your
job is to make sure that the PPM levels in your water solution are on point so you’re
not under- or over-feeding your plants. While it’s an easy concept to understand on
the surface, it’s a little more complicated when you have to adjust elements.
Now, pH plays a huge factor in PPM levels because even though you may have the correct
PPM reading, some of the particles- and the concentration of those particles- can be
harmful for your plants.
For example, let’s say your plants need to be at a PPM level of 700. You mix your
solution and you get a PPM reading of 700 but your pH is around 4.5. That means that
the majority of the available food for your plants is likely to have lots of heavy
metals in it, which will quickly toxify the plant. You’ll need to adjust the pH level
of your solution to make sure you’re not toxifying your plants.
“But won’t that throw my PPM levels off because you’re adding particles to your feeding
solution?” It can, and that’s what’s so tricky about PPM and pH levels: When you adjust
one you usually have to adjust the other, which can be simple or a huge pain depending
on the water and nutrients you’re feeding your plants.
Common PPM Readings
These readings reflect the PPM your water should have at a given stage of growth
? Seedlings: 100-250 (nutrients aren’t really needed here, hence there’s not a
lot of particles needed)
? First Half of Vegging Cycle: 300-400 (this is usually after you transplant,
which still don’t require many nutrients)
? Second Half of Vegging: 450-700 (you’ll start giving your plants more nutrients
at this stage)
? First Half of Flowering: 750-950 (your plants will be eating more as they grow,
so they’ll be taking in more nutrients)
? Second Half of Flowering: 1000-1600 (this is when your plant’s eating the most,
especially if you give it additives)
? End of Flower, Entering Harvest: As close to 0 as possible (this is when you’ll
be flushing your plants, so you don’t want there to be a lot of particles left over)
Adjusting pH Levels
When it comes to feeding plants there’s two ways of looking at it: homemade or store bought.
Same goes with balancing your pH: you can either purchase a pH buffer from a store or you
can use ingredients you can find around your home or in the grocery store– but both come
with their advantages and disadvantages.
Homemade pH Buffers
? Advantage: If pH levels are low you can use a little citric acid or even white
vinegar to help bring your water’s pH down. When you need to raise your pH levels you
can use a little bit of baking soda in your solution and bring those readings back up.
This will cost you less than picking up a buffering solution.
? Disadvantage: The issue with using these solutions is that they don’t work for
very long. You’ll find yourself having to add a little lemon juice every other day, then
having to use a little baking soda to even things out. Moreover, we’ve also heard of
growers using these ingredients and seeing severe spikes in pH, which if not handled
properly and quickly and bring your grow to a halt.
Premade pH Buffers
? Advantage: Most hydroponic companies out there will have pH buffers, usually
called . They’re much easier to use than citric acid or white vinegar mixes. They’re
designed raise and lower the pH of your water while keeping your water’s pH levels
balanced for longer than it would be without them.
? Disadvantage: As we’ve always mentioned, easier usually means more expensive.
These solutions usually won’t cost you an arm and a leg, but they’re definitely something
you can’t simply make at home and will cost some money.
Adjusting PPM Levels
Before you start adjusting your PPM levels, you’ll first want to make sure your tap water
is ready to feed your plants. That means you’ll want to adjust the PPM of your base water
before you start feeding it to your plants Now, any time you add anything in to your watering
solution, you’ll be adding more particles in to it, so keep an eye out on your PPM levels at
all times.
? To rid your water of too many particles you can use things like a carbon filter or a
reverse osmosis machine to clean your water. However, many growers agree that most tap water
has helpful minerals (like calcium and magnesium) that actually help plants.
? During and after the vegging stage, your plants will want more out of their feedings
so filtering isn’t really necessary. That’s why we recommend only using filters at the
beginning of the plants life when low PPM readings are needed
? For a quick fix when PPM’s are high just add a bit of fresh water with a good pH
level and watch them drop. Filtered, pH’ed water is great when things get a little too
much in your reservoirs.
? When readings are low it’s usually time to feed your plants. When you add nutrients
to your feeding solution your PPM’s will go back up, and when your PPM’s and pH’s are in
balance your plants are going to be happy and healthy.
? Just remember that these readings need constant adjustment, so if you haven’t been
keeping a close eye on your plant’s PPM and pH levels there’s not better time to start than now.


This is great stuff thank you very much everyone.


your very welcome/ We are here to help when ever we can.

B Safe

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This was very help full by all thanks…

I’d like to piggy back off this. My FFOF runoff was 2100 when all I used was RO water the first four weeks. I called FF and they said not to measure or worry about my ppm runoff. I have a hard time knowing what to put in when my readings are high during flower. How do I know if there’s a lockout? I do slurry testing and pH is fine but it’s starting to look like shit.

The pics of those leaves whats the cause

looks like Nut burn

Too much nutes,stop feeding them,just give water,i had same issue this MG nutes,mine spieked at 1 plant 4559ppm
and second plant was
And thats what you get for being idiot and overfeed the girls,so just flash them now and pray for not getting any issues in the future.

Wow the info varies from youtuber to said forums … some say Veg should be 500 in 500 out (runoff) and up that a little till flowering begins at 1000ppm and then mid flower heavy feeding between 1000-1800… o.O who to follow?

I believe 800 to 1,000 in would be sufficient and maybe 1,200 out should be a little more on the out as there should be some build up in the soil or medium

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I used fox farm, feed at like 2 gallons for a 5 gallon bucket. I like to bounce back and fourth between 2 and 3. Make sure when you water you have alot of run off to get salts out , and help from nutrient build up from occuring.