Stupid question
- Thread starter Ahk83
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Do you mean EC? It stands for electrical conductivity. A measure of how much "stuff" is dissolved in your water. Ppm is calculated from EC but is sometimes easier to grasp the idea of.
It's not important at all. They are 3 ridiculously over-used letters. Sheee-it, I abuse them regularly. EC=healthy plants.
Lmao hell then what’s a good EC
That’s pretty dope I’m bout to look it up
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EC is a measure of how much salty-stuff is dissolved in your water. Specifically, it's a measurement of the electrical conductivity of the solution. It's expressed in milli- or micro- Siemens per cm, i.e., uS/cm or mS/cm. Siemens is the inverse of Ohms, which is a measurement of how something may "resist" electrical current. Siemens simply reflects how much something "conducts" electrical current. Salts in water = conductive solution that can be quantified.
Another common unit to represent how much salty-stuff is dissolved in your water is ppm (parts per million). EC and ppm are related, although the conversion may differ depending on what part of the world you live in. In most places, 500 ppm = 1.0 mS/cm = 1000 uS/cm. In other parts of the world, 700 ppm = 1.0 mS/cm = 1000 uS/cm. As a result, I prefer to talk about EC as there's no ambiguity. When talking about ppm, it's often necessary to be specific as to whether you're talking about the 500-scale (also called the 'Hanna' scale), or the 700-scale (also called the 'Truncheon' scale). For the values below, I'm using the 500/Hanna scale...
Measuring EC/ppm is often done with a TDS ('total dissolved solids') pen.
I encourage you to look up EC/ppm targets for various stages of cannabis growth, especially as it pertains to autoflowers. There is no "one size fits all" value. Some strains will require higher ppm/EC, others less so. In the case of autoflowers, Man O' Green suggests ~650ppm or 1.3EC as a good upper target for established autos in veg through to flower. I agree with this number from personal experience. Check out his tutorial here: https://www.autoflower.org/threads/a-word-on-nutrients.82004/
The medium will also come into play, as will watering frequency. High-frequency fertigation in coco generally requires less ppm/EC. However, feeding once a week in soil might require high ppm/EC. Also, generally, bigger plants means higher nutrient requirements.
A good nutrient feedchart will typically show EC/ppm targets by week. For example, the latest General Hydroponics feedcharts are available in three-versions: (1) aggressive feeds which max out at 2.4 mS/cm or 1200ppm; (2) medium feeds which max out at 2.0 mS/cm or 1000ppm, and (3) light feeds which max out at 1.8 mS/cm or 900ppm. Each of this values includes up to 200ppm starting water, which I’ll talk about below, and again, these are for photoperiods. For autos you typically hear people talk about "half strength nutes" in the order of 500-650ppm excluding their starting water. Personally, I'm not a huge fan describing nute strength by 'half' or 'quarter' strength as there's so much variance between feedcharts. Best to go by ppm/EC and keep things specific. The article above is a great starting point for EC/ppm targets for autos, and feedcharts in general are a good starting point for photoperiods.
TDS pens are also handy because they will inform you on what's in your plain water. Generally speaking, if your tap water exceeds 200 ppm (0.4 mS/cm), you may want to consider treating it. This is a rough number and some folks will probably disagree with it, but either way, it's good to know your starting water quality.
Cheers,
tron
PS - Disregard the above if you were asking about the Latin expression “et cetera”, hehe.
Another common unit to represent how much salty-stuff is dissolved in your water is ppm (parts per million). EC and ppm are related, although the conversion may differ depending on what part of the world you live in. In most places, 500 ppm = 1.0 mS/cm = 1000 uS/cm. In other parts of the world, 700 ppm = 1.0 mS/cm = 1000 uS/cm. As a result, I prefer to talk about EC as there's no ambiguity. When talking about ppm, it's often necessary to be specific as to whether you're talking about the 500-scale (also called the 'Hanna' scale), or the 700-scale (also called the 'Truncheon' scale). For the values below, I'm using the 500/Hanna scale...
Measuring EC/ppm is often done with a TDS ('total dissolved solids') pen.
I encourage you to look up EC/ppm targets for various stages of cannabis growth, especially as it pertains to autoflowers. There is no "one size fits all" value. Some strains will require higher ppm/EC, others less so. In the case of autoflowers, Man O' Green suggests ~650ppm or 1.3EC as a good upper target for established autos in veg through to flower. I agree with this number from personal experience. Check out his tutorial here: https://www.autoflower.org/threads/a-word-on-nutrients.82004/
The medium will also come into play, as will watering frequency. High-frequency fertigation in coco generally requires less ppm/EC. However, feeding once a week in soil might require high ppm/EC. Also, generally, bigger plants means higher nutrient requirements.
A good nutrient feedchart will typically show EC/ppm targets by week. For example, the latest General Hydroponics feedcharts are available in three-versions: (1) aggressive feeds which max out at 2.4 mS/cm or 1200ppm; (2) medium feeds which max out at 2.0 mS/cm or 1000ppm, and (3) light feeds which max out at 1.8 mS/cm or 900ppm. Each of this values includes up to 200ppm starting water, which I’ll talk about below, and again, these are for photoperiods. For autos you typically hear people talk about "half strength nutes" in the order of 500-650ppm excluding their starting water. Personally, I'm not a huge fan describing nute strength by 'half' or 'quarter' strength as there's so much variance between feedcharts. Best to go by ppm/EC and keep things specific. The article above is a great starting point for EC/ppm targets for autos, and feedcharts in general are a good starting point for photoperiods.
TDS pens are also handy because they will inform you on what's in your plain water. Generally speaking, if your tap water exceeds 200 ppm (0.4 mS/cm), you may want to consider treating it. This is a rough number and some folks will probably disagree with it, but either way, it's good to know your starting water quality.
Cheers,
tron
PS - Disregard the above if you were asking about the Latin expression “et cetera”, hehe.
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So tron that is some great knowledge man really informative stuff there. I’m about to go and check out that link you gave me.
I just want to say thank you for everyone trying to help me out here this community are so freakin awesome and helpful. I never knew there was a place like this to help people out just for the sake of helping people try to get the best out of their grows so like I said thank you all. I’ll post some pics of my grow for y’all to see…thanks again y’all
They look quite happy! Strong work.
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