EC/CF or TDS/PPM

[GenX Toker]

Well I was on another forum and saw a thread about this subject. I did not want to join yet another forum and yet I felt that this topic was worth mentioning so I decided to share it here.
There are arguments out there as which meter type to purchase weather it be a TDS/PPM meter or an EC/CF meter. (Yes I know that there are combo meters out there but that is not what I'm on about so bare with me please.)
Some are saying that EC is more accurate than TDS or vise versa, when in truth they are both within 10 % of each other. You can sit and do the equations all day long yourself if like. Just make sure you know your meters conversions as they are different from manufacturer to manufacturer.
None of this however really needs to be of concern. Just make sure you have a meter that reads from 0 to 1999 meter. As you check your solutions take note of your plants health and reactions to different levels and keep them in the same range. It wont matter if its EC , TDS, or MOON UNITS as long as it stays within your target range.




There is an attached excel document (converted to pdf ) that I use to monitor and control my nutes,temp and pH. I have adapted this chart from an SPC (Statistical Process Control) chart from work.
The ranges in this chart are from the books "GROWING ELITE MARIJUANA" and
"THE CANNABIS GROW BIBLE". However the values I have entered are all arbitrary to be used as an example.
I know it seems a bit much, but it has really helped me keep everything in check.
If anyone would like to have this SPC chart just let me know and I would be happy to send it your way.
I know its set up in hours but that is easily changed.

 

[kushtrees]

IMO it doesn't matter how YOU measure for yourself if its working. For comparison reasons and talking to other people I think EC (or CF same thing) is better because you do not have to know if someone is using 700 or 500 conversion, I even know some people who do 600.

What ever works best for you go for it. But if we're discussing things might as well discuss things in terms of a constant where we dnt have to continually confirm conversion.

On another note most TDS meters just measure EC and use an equation to estimate TDS from that. From what I hear a true TDS meter is much more expensive, dnt quote me on that though

 

[ttystikk]

A true TDS 'meter' is a whole different animal and would be more useful to a chemist than to us hobbyists. These boil away the solution and weigh what's left. All of the meters we use measure the Electrical Conductivity (EC) of the solution- and of course, not all materials conduct electricity through a water medium equally. No matter what the scale says, they ALL work this way and then convert the displayed value to whatever scale they're designed for. Because of this, I've found it more useful and less confusing to just use EC all the time, and let the reader make any conversions they might like for themselves. Likewise, I ask others to provide solution strength readings in EC, so I can be sure I don't make conversion errors of my own.

I have a BlueLab Truncheon TDS meter that has some 6 different scales printed all the way around the device. This allows you to read the meter in any scale you want and even convert quickly and visually between them. It works great for reading your EC, too!

 

[kushtrees]

Completely agree. love my blue lab truncheon

 

[GenX Toker]

Okay everyone. I am neither confirming nor denying any of your statements. All I am saying is that it does not matter what you use scale wise. (yes you will want a good meter) All I am saying is that whichever you use just make sure to keep your reading in a specific range during the relative growth cycle.
I dont know about everyone else here but I for one do not have the equipment to measure true TDS as stated by ttystikk. Nor do I feel it is necessary.
I am not trying to start any arguments but I was once told that "It is not so much how good the equipment is that you use, rather How good you use the equipment that you have"

 

[ttystikk]

Okay everyone. I am neither confirming nor denying any of your statements. All I am saying is that it does not matter what you use scale wise. (yes you will want a good meter) All I am saying is that whichever you use just make sure to keep your reading in a specific range during the relative growth cycle.
I dont know about everyone else here but I for one do not have the equipment to measure true TDS as stated by ttystikk. Nor do I feel it is necessary.
I am not trying to start any arguments but I was once told that "It is not so much how good the equipment is that you use, rather How good you use the equipment that you have"

I gotta quibble with a few of these points. First, the whole point of scales is to be able to quantify what you're doing... so others can learn from/comment on/make suggestions about what you do. If people can't figure out what each other are doing because of scale incompatibility issues, that's bad- and unnecessary. In other wqords, you can call an apple by any other name and it will still taste just as sweet, but don't expect anyone else to know what you're talking about!

Second, good equipment is a requirement for good results. Try using a bad pH meter and see how far you get! Yes, hard work and good practices are also critical, but don't discount the value of top quality gear.

 

[GenX Toker]

You seem to be an intelligent person TTY and I am not disagreeing with you on the fact that for comparative results then we all need to be on the same page, this is true. However until there is a standardized way of doing these things then we are pretty much stuck with what we have.
I am not saying that the way I do things is the be all end all and everyone else is wrong (I hate it when people do that.) I agree 100 % that we need to understand each others methods in order to make somewhat intelligent comments/suggestions.
As far as the proper tools go, well I know the importance of "the right tool for the job" I was merely trying to state that even with cheaper tools (so long as they are at least consistent)
one can achieve very good results. (and no, they may or may not be comparable to others results. But they will get you in the ball park.
There is no substitute for diligently keeping notes and never forgetting to check your references.
And yes I DO wish there were only one meter on the market. Or at the very least that they would all work the same.
Until that day perhaps this will help.

 

[tedsprogz]

^ Tyystikk YES. Like you said before Genx, as long as you stay in the range you're good...but how do you know what range you're at if your meter is off?
That's why a standard really does matter.
A good quality meter too!
Yes you can do a great job if you were all on your own and you found your sweet spot with your meter.
But now lets say its faulty and reads a few whole points higher on your meter.
Now lets say your sweet spot range would be 2.6-3.2 on your meter.
Then you come on here with pics and all saying your EC is 2.6-3.2 and your plants love it. Someone else reads it and tries it.
That's why a good meter and a standard unit of measure is important...
But you are right in the points you made.

 

[GenX Toker]

Well fk a duck had some trouble inserting my image on the last post.....

 

[tedsprogz]

thats the only point tyy was making, not that you cant grow well without it.

 

[tedsprogz]

u cant post p h to bucket pics but we know how to replace the url so im sure he seen it. just replace invalid with the word

 

[GenX Toker]

^ Tyystikk YES. Like you said before Genx, as long as you stay in the range you're good...but how do you know what range you're at if your meter is off?
That's why a standard really does matter.
A good quality meter too!
Yes you can do a great job if you were all on your own and you found your sweet spot with your meter.
But now lets say its faulty and reads a few whole points higher on your meter.
Now lets say your sweet spot range would be 2.6-3.2 on your meter.
Then you come on here with pics and all saying your EC is 2.6-3.2 and your plants love it. Someone else reads it and tries it.
That's why a good meter and a standard unit of measure is important...
But you are right in the points you made.

Ya Ted I agree. So we just state that our individual results are compliments of meter x,y or z.
Just an honest question then. What would everyone prefer that this "standard" be??

 

[GenX Toker]

Cant paste from ph bucket eh?? hmmm strange. oh well i got it up there just in the wrong place.........

 

[GenX Toker]

LMAO cant remember last time I typed this much. Wife is gonna think I'm chatting up some hottie.

 

[tedsprogz]

everyone has a different wallet...i have a hanna pen that only reads ppm and ph and uS...

 

[homebrew420]

I used to use a Hanna meter worked fine is the way for me. ppm worked for a long time. Bottom line person preference. and if you dont have one ass yet purchase a meter that will read both.

Peace

 

[LexLuthor]

Does anyone know why they have different conversion rates for EC to PPM?? It would be easier with only 1 conversion scale.

 

[ri420patient]

Well I was on another forum and saw a thread about this subject. I did not want to join yet another forum and yet I felt that this topic was worth mentioning so I decided to share it here.
There are arguments out there as which meter type to purchase weather it be a TDS/PPM meter or an EC/CF meter. (Yes I know that there are combo meters out there but that is not what I'm on about so bare with me please.)
Some are saying that EC is more accurate than TDS or vise versa, when in truth they are both within 10 % of each other. You can sit and do the equations all day long yourself if like. Just make sure you know your meters conversions as they are different from manufacturer to manufacturer.
None of this however really needs to be of concern. Just make sure you have a meter that reads from 0 to 1999 meter. As you check your solutions take note of your plants health and reactions to different levels and keep them in the same range. It wont matter if its EC , TDS, or MOON UNITS as long as it stays within your target range.




There is an attached excel document (converted to pdf ) that I use to monitor and control my nutes,temp and pH. I have adapted this chart from an SPC (Statistical Process Control) chart from work.
The ranges in this chart are from the books "GROWING ELITE MARIJUANA" and
"THE CANNABIS GROW BIBLE". However the values I have entered are all arbitrary to be used as an example.
I know it seems a bit much, but it has really helped me keep everything in check.
If anyone would like to have this SPC chart just let me know and I would be happy to send it your way.
I know its set up in hours but that is easily changed.

i would like this thanks