5.8PH is the ball park for all coco grows and is a good PH for any coco grower.
You can stick religiously to 5.8PH in coco and get good results every time.
At the start of a grow seedling tend to like it a little bit more acidic and towards the end of the grow they can take a bit more alkaline, as it make the calcium and magnesium more available.
A wet/dry cycle (which cannabis likes) makes the PH fluctuate too but not too much, which also makes the various chemicals in the feed available.
It is only a subtle shift but one that growing in coco likes as coco likes to hold on to calcium and lock it up.
Using properly rinsed & buffered coco helps to reduce this but using full spectrum lighting like LED, LEP & CMH enable the plant to use nutrients at a higher rate, which can lead to CalMag/Iron deficiency.
So 5.8PH is the ideal middle ground for PHing feeds in coco but allowing it to range from 5.7 to 6.1 occasionally, with a wet dry cycle will allow the plants to get the full spectrum of nutrients.
What "EC" or which "PPM scale"nutrient strength you use, well that's down to what each strain likes, some can go strong whilst other strain only like light feeding.
It's all about feeling your way forwards and seeing if they are demanding to be fed more.
If you grow a strain numerous times then you get to dial in what it likes, the problem these days is there are so many strains on the market, virtually no one except commercial growers, grow the same strain twice. This means every grow we are feeling out way forwards, often using rules of thumb as a guide, which we tweek in response to our plants needs.
One thing to remember about PPM is there are several different scales, such as the 500 scale (Hanna) the 640 scale (Eutech) the 700 scale (Truncheon).ppm is known as dimensionless quantities; that is, they are pure numbers with no associated units of measurement. A mass concentration of 2mg/kg - 2 parts per million - 2ppm - 2 x 10 -6. There are many different scales used for different industries around the world and for many different reasons!
EC stands for Electrical Conductivity and is measured in mS/cm or millisiemens per centimeter. TDS stands for Total Dissolved Solids and is measured in PPM or parts per million. TDS is acquired by taking the EC value and performing a calculation to determine the TDS value.
To find out what CF is in EC / by 10 and EC to CF * by 10.
North america tends to use the 500 scale , whilst europe tends to use the 700 scale.
The 700 scale & the 500 scale are the most frequently used scales.
here is how to find the PPM of each of the 500 & 700 scales into EC and vice versa,
2.4EC x 500 = 1200ppm (500 scale) or 1200ppm / 500 = 2.4EC
2.4EC x 700 = 1680ppm (700 scale) or 1680ppm / 700 = 2.4EC
WHAT PPM SCALE IS YOUR NUTRIENT FORMULA REFERRING TO?
Manufacturer PPM Scales (North american companies may tend to use the 500 scale and European companies tend to use the 700 scale. check with the manufacturer if you are unsure)
Advanced Nutrients 700 scale
Botanicare 700 scale
Cutting Edge Solutions 500 scale
Dutch Master 500 scale
Dyna-Gro 500 scale
FoxFarm 700 scale using dechlorinated tap water
General Hydroponics 500 scale using reverse osmosis water
General Organics 500 scale using reverse osmosis water
House & Garden 700 scale
Humboldt Nutrients 500 scale
Hydro Organics/ Earth Juice 500 scale
Miller Chemical & Fertilizer
Nectar for the Gods 700 scale
Rock Nutrients 700 scale
Roots Organics 500 scale
Soul Synthetics 500 scale
Technaflora 500 scale
Here is a chart that shows which meters measures which scales (Nb. Bluelabs "Truncheon" measures EC, 500 scale and 700 scale) which is why i have one.
To increase the size of the chart open it in another window and using CTRL and mouse wheel to magnify. Mac users, i have no idea how to make it bigger, sorry.
View attachment 1060425
I may have got carried away a bit there but it is all useful knowledge and giving someone a PPM strength without stating which PPM scale you are using could cause disastrous effect on another persons grow, if they are using a different scale!
Here is a EC, CF & 500, 640 & 700 scale chart conversion.
View attachment 1060427
You will notice if you look at 1.0EC and follow across the chart you will see the 500 scale, the 640 scale & the 700 scale etc