EC vs PPM

[Guest]

Hey, I just had a quick question. I finally got my ec/ppm/ph meter up and running and wanted to know how EC ='s ppm? I am pretty sure my meter only does PPM, I have this model here;

http://www.bustan.ca/product_detail.asp?menuID=3&SID=23&PID=83

Up until now I have been going strictly on PH and the force, but some of my girls have a bit of burn so I want to know the full story!

Anyways, I know there is some kind of conversion factor involved in this, I believe my meter is set to .5 currently. Can someone give me some pointers on converting my EC readings to PPM readings? Thanks guys

 

[pontiac]

 

[kokua]

its all just a form of reference for you really. The real advantage a tds/ppm/ec meter gives is only seen over time. If your tds/ppm/ec is rising over time, your nutrient is too high. The plant is taking in more water and leaving excess nutrient behind making the concentration rise. If the tds/ppm/ec levels drop over time that means your nutrient concentration is too low. The plant is taking in more nutrient than water and the concenration drop. What you want to see is a constant tds/ppm/ec reading. This means your plants are taking in and using the nutrient at the same level as they are water. When this happens the water level in your reservoir will drop but the tds/ppm/ec levels remain constant. It is obvious why this is most beneficial scenerio You want to avoid having to add nutrient or water if you can. When you get her there....you gotta ride it. Its like a wave. When a system is really dialed in you can go a whole run without res changes...



On a another note...I think everyone should use ec. There is no conversion factors...no chance for confusions or miscalculations. Ec is ec is ec. Just my 2 cent

 

[AbaZabba]

Good chart pontiac, seems to be very useful if you have any of those brand pens hehe.
The problem I'm facing is finding the EC for my Sunleaves ppm pen, it does not read EC. I received this pen as a gift and really like the ability but was curious if anyone knew the conversion for EC to PPM with this meter?

the model is:

http://www.sunleaves.com/detail.asp?sku=STD500#

If anyone has an idea what the conversion for this pen is that would be greatly appreciated. If not, o well i'll still use it and keep it @ ~900

 

[pico]

I second Kokua's motion to use only EC. The ppms pens should tell you the conversion on the unit at least.

Nothing worse then a .7 conversion guy telling the .5 conversion guy how high to run his nutes. 1400ppm @ .7 conversion is EC 2.0 1400ppm @ .5 conversion is EC 2.8


Or better yet, just get a Blue Labs Truncheon meter. It is the best meter I have ever owned. It displays EC, CF, PPM .5/.7, TDS. It just has a series of lights at an accuracy of .1 EC. Very easy to read.

 

[Moppel]

thnx pontiac. but quiet confusing , different ppm with different meters.

 

[pontiac]

Its important to note that ALMOST ALL AMERICAN MANUFACTURERS uses the .5 Conversion factor by default (if the meter only measures tds). Which means that HM DIGITAL, HANNA, MILWUAKE, OAKTON, SUNLEAVES etc. uses the .5 factor. Most Euro models uses the .7 conversion factor; i rarley see the .64 conversion factor in use. Hope this helps.

 

[Guest]

Great chart Pontiac, thank you very much!

Hey Kokua, thanks for the info! At the present time I am hand watering on a daily basis with 2-3 different nute mixes between veg and flower. In the future I would love to move to a res and drip system but it will require a bit of a re-design as my current grow space has no room for res's and no way to deal with run off. I will have to do something sooner than later though, the wife is not happy about us not being able to go on vacation because the plants need to get water'd

I got my meter out and up and running @ the .5 conversion rate, things seem ok so far, I will be into my flower cab right away to see how yesterdays nutes were received, @ about 1.3 EC in week 3 of flower. Thanks guys!

 

[gaiusmarius]

I second Kokua's motion to use only EC. The ppms pens should tell you the conversion on the unit at least.

Nothing worse then a .7 conversion guy telling the .5 conversion guy how high to run his nutes. 1400ppm @ .7 conversion is EC 2.0 1400ppm @ .5 conversion is EC 2.8


Or better yet, just get a Blue Labs Truncheon meter. It is the best meter I have ever owned. It displays EC, CF, PPM .5/.7, TDS. It just has a series of lights at an accuracy of .1 EC. Very easy to read.

so true, that is why one should be very careful about telling another grower what ec to use. i tend to talk about ml of nutrient per lt if i want to be very clear.

it's a good chart though

 

[Guest]

i need to print that chart out thanx

 

[Guest]

whats a good baseline ppm to start out for

seedlings
veg
flower

i know it might b strain dependent, so i guess i should start out low n work my way up A?

 

[Guest]

whats a good baseline ppm to start out for

Perfect example... ppms for .5 or .7?

 

[Guest]

oops lol

.5 good sir

 

[Protostele]

I have the Milwuake pen and until I read Pontiac's post I didn't know for sure what the conversion factor was for it, as I don't ever recall it saying in the literature that came with it.

I determined which column in the above chart applied to my pen after switching to Canna Coco Nutrients by using the mixing charts in Canna's colourful brochures. Since I bought the full line of Canna nutrients I was able to mix a batch according to their chart and using rain water collected off a steel roof, as our well water measures about 700 ppm and is not fit for plants, let alone human consumption.

Canna's charts indicated I should measure 910 or EC 1.3 when using 8 ml of A, 8 ml of B, 2 ml of rhizotonic, 8 ml of cannazym and 6 ml of PK13/14 for each US gallon. It was obvious by the above chart that Canna was giving the ppm that a truncheon pen would read and when I measured my mixture the pen was reading 700 which is very close to the .5 conversion according to the same chart. This pen only reads to the nearest 100 ppm so I figured it was close enough to the 650 ppm that I should be using the .5 conversion. I was very accurate in mixing as I use a syringe to measure.

I did think it odd that Canna made their mixing charts using a combination of metric and US gallons. It would make more sense to keep it all metric but perhaps we are getting brochures made for the US market.

As I drip and/or manually water to waste, the pen is really not needed anymore, but I still like to check while mixing, just from habit.

Protostele

 

[Kenny Lingus]

I have the Milwuake pen and until I read Pontiac's post I didn't know for sure what the conversion factor was for it, as I don't ever recall it saying in the literature that came with it.

I determined which column in the above chart applied to my pen after switching to Canna Coco Nutrients by using the mixing charts in Canna's colourful brochures. Since I bought the full line of Canna nutrients I was able to mix a batch according to their chart and using rain water collected off a steel roof, as our well water measures about 700 ppm and is not fit for plants, let alone human consumption.

Canna's charts indicated I should measure 910 or EC 1.3 when using 8 ml of A, 8 ml of B, 2 ml of rhizotonic, 8 ml of cannazym and 6 ml of PK13/14 for each US gallon. It was obvious by the above chart that Canna was giving the ppm that a truncheon pen would read and when I measured my mixture the pen was reading 700 which is very close to the .5 conversion according to the same chart. This pen only reads to the nearest 100 ppm so I figured it was close enough to the 650 ppm that I should be using the .5 conversion. I was very accurate in mixing as I use a syringe to measure.

I did think it odd that Canna made their mixing charts using a combination of metric and US gallons. It would make more sense to keep it all metric but perhaps we are getting brochures made for the US market.

As I drip and/or manually water to waste, the pen is really not needed anymore, but I still like to check while mixing, just from habit.

Protostele

This was very important info! I've also been twisting my brain to find out what is what.
I use a Milwaukee EC meter and pH-meter (Great service too from these guys, opposed to BlueLab denying me new probe on guarantee without even seeing it first.). Well well, the Milwaukke site only mentioned conversion for pH meters, so I wondered again... THen I saw Advanced Nute calc saying they use seven conversion and their ppm value divided on 700 would give EC level. Easy huh? (Is it the nutes conversion or the meters conversion that is important when measuring EC???)

 

[ShroomDr]

you should really just figure out what the ec is, and use that. it never changes, and you can figure out what 'ppm scale' the particular company is using.

 

[bounty29]

Put me down as another vote to only use EC

 

[Guest]

Put me down as another vote to only use EC

Haha...I still find it amazing the whole ppm/EC confusion. Very quickly after starting hydro I ditched PPM's and any time I talk with someone and ppm's comes up I create another convert :wink:. It's still important to know about ppm's...I had a buddy get a $25 Hanna 999 max ppm pen to start him out on hydro and the thing works fantastic. Just gotta know how to convert. I've seen people fry grows switching over to AN that went by the label recommendations for dosage based on ppm's.

This thread has some good basic info and glad it came back to life for all those newer to see.

 

[Guest]

ec or cf ,,its only a .