To EC or Not To EC - What Really Is the Question?

Earlier this month I was asked to pen an article for this magazine on a topic which I felt would be relevant to the greenhouse and hydroponic industry.

On the ride home that night I thought, "What a golden opportunity, to sing the praise for our company, and just maybe, even get a plug in for myself out of this deal."

The more I thought about this, the better it all sounded. First I had visions about all of the potential business I was going to round up by writing a big time article. Imagine all the results I was going to achieve. Then my mind started to really spin, seeing all those benefits that come my way; fame, fortune, guest appearances on talk shows, maybe a book offer. Whoa there fellow-what a life it was going to be!

Finally, with alarming clarity, my brain started to tune into the screaming of the clock radio and as I gave the box a hard smack, sending it tumbling, I gave my head a good shake, and reality started to push out all of the glorious thoughts which had momentarily flooded my dreams. The last image I saw was a reality gremlin singing "I owe, I owe, so its off to work I go." So off I went, grumbling, to start another day in the shower.

A short time later, I was cornered by Jim Jesson at the Can West Hort show, "Hey there, don't forget about our article-oh and I would love to have it for the first week of October you know." He has such a delicate way of asking for things. And of course, I answered in my eternally up beat and cooperative voice, "YOU BET JIM!"

So, here I am, clattering away on a train, somewhere between Montreal and Toronto, gathering my thoughts to extoll the virtues of what I believe to be a major, crucial, frustrating, sometimes costly, and always a pesky issue. The issue that I am talking about is the various forms of measurment for testing or measuring disolved solids in an aqueous solution.

To begin, we know by definition that electric conductivity (EC) is the ability of a substance to conduct an electric current, and that the measure of (TDS) is the amount of solids dissolved into an aqueous solution. In aqueous solutions, conductivity is directly proportional to the concentration of dissolved solids, so the higher the concentration of solids, the higher the conductivity.

Now, what's the big deal, one may ask. Just shoot a little current through some solution, measure some positive and negative ions, look at the reading on one of our Hanna meters, high or low could mean good or bad and presto, you're done! Then you're off to the next series of tests. If all goes well, you're out of there by five o'clock. SCREECH go the brakes as the logic wheels fall off the cart. It is at this point that the simplicity and precision of the new age, butts up against the some of the confusion and inaccuracy of days gone by, and logic goes right out the window. What I am talking about is the use by some growers, of the EC method to measure and calculate concentrations of fertilizer versus the use of the confounding, and not so clear system of measuring the conductivity, then transforming this data to either PPM, PPT, G/L, or MG/L.

Even writing this, I am reminded of the conversations I used to have with my daughter while she was growing up and going through school. "Hey Dad, how hot is it outside," was her question, and I would answer her without hesitation, "why it must be about 70? my dear."

"Wow, it must be really, really hot outside, Dad," she would answer, with a very perplexed look on her face. I would look at her, wondering what the problem was, and then it would hit me. " Well my dear, that would be about 20?C, you won't need your coat on today." This conclusion, of course, was after some mind racing to come up with a conversion factor in order to put my old temperature rating into a new and improved measure that the new generation could understand. You see, even I sometimes look out my window, read the Farenheit side of the thermometer, get the brain cells humming, do a fast conversion, and spit out the temperature in Celsius. Not the best way, leaves room to err, but then again, it is never life threatening for me if I miss by a degree or three. Distance posed the same amount of frustration when explaining something to my kids; miles versus kilometres, inches and centimetres. As well, units of weight were a nuisance when the need to talk pound or kilos came up. My memory seems to recall a serious incident that arose when the conversions from pound to kilos were not carried out correctly, and an airline pilot erroneously converted his fuel load from one to the other, and ended up short of fuel for the flight distance required. "Ran out of gas" was probably not what the passengers wanted to hear on that trip and the whole event would have been aviodable if we were working in one, easy to use scale of measurement.

So this is where we return to the dicussion over the EC versus TDS measurement system. If our industry would just take a stand, get over the fear of ruffling feathers, and say "OK, at a certain date in the future, (this may be by secret vote) we are going to use, manufacture, and sell fertilizers and measuring devices that are based on the EC scales of measurement. All measurements from that day forth are taken in EC. What would be the worst thing that could happen? Here is one possible scenarios:

1. A lot of phones would be ringing at the company reps offices to find out what happened to the ratings on the back of fertilizer container and meter boxes.
2. This would lead to more company training seminars being given to clients by company reps.
3. This would mean reps spending more quality time with customers and solving problems together! (this could be totally shocking)

But this scene would eventually straighten itself out and the world would get back to normal.

Now, to the issue of confusion between PPM, PPT, G/L, and MG/L and any others that might get lumped into the group; you can only begin to imagine the look of disdain on a clients face the other day when he approached me at a trade show about a certain meter and I promptly returned his query with "was that a 0.5 factor of conversion or a 0.7 factor of conversion."

You see, just when you thought there was a little light at the end of the tunnel, and you were beginning to understand the intricacies of the PPM and G/L story, someone went and slammed you with two more things to convert from and to.

As a manufacturer of high precision instruments, how do you think we at Hanna feel when a client comes to us, growling about how his *!x @%?$ meter can't be calibrated correctly, he just bought the bloody thing, wants his money back, and hates all of humanity equally. I kow he would like to choke me slowly in order to extract his vengance. Now I have to slowly dance around his questions, trying to find out if the meter he is using is a EC or TDS version. Then did he switch to a 0.5 from a 0.7 conversion factor or what? At this point, I scratch my head, and wonder what life would be like with out such complications.

You have to realize that I do understand the consumers point of view. I am in the same boat, when it comes to purchasing things. When I go to my local retailer or garden center, I am not looking for the new wonder fertilizer that matches meter ABC with the 0.7 factor of conversion to correspond with TDS 442 rating of the new products. No, no, no. What I am doing is zeroing in on the blue meter I bought last time, fouth row from the front of the store, turn right, second shelf from the bottom, pay for it and get on with the day. If the industry just said "All meters in all mS and 5S, no more TDS, customers might just come in, pick up two-three more containers of fertilizer than usual, and off they would go to take care of their crops, increase their yield, make more money, and keep the economy rolling.

"Speaking of money, did you know that using EC versus TDS products can and will ultimately save you money too?" "How so?" you may ask. Well, first and the most obvious way, is to reduce the time you spend standing around scratching your head, wondering why you can't calibrate a meter you just bought...duh!! I wonder if it could be PPM or PPT or MG/L or just what the?

When you could be springing into action, taking a quick EC reading, ready to tackle that pesky disease problem attacking your crops, or hauling your record crop off to market to sell for the big bucks! This is instant feedback that you are saving money and that it is a better system.

The other way using EC based products versus TDS is in the accuracy it will bring to your operation. Picture this; you, the grower, have been using a 0.5 factor rule. You have decided that this is the day you will purchase a new measuring device for your operation. You carefully study the meters available, selecting a shiney new model. You run it by the cashier beaming with pride. Upon arriving at your office, you remove the meter from its package and with all of the pride of a new car owner, you skim through the owners manual. Brushing over the details, anxious to use your new meter in the first measurements of its new life.

You begin with one sample, then another, mixing, sampling, getting the same TDS readings you usually get, and soon you have the recipe perfected, the same batch that brought you production success in the past. But is it really?

You happen to glance at the new container of nutrients you just opened. The kind you have been using for some time. You are the kind of person who takes pride in your ability to make detailed records, to take exacting notes of operation, to measure twice and cut once, and to duplicate your method of operation.

But something is wrong, not as it should be. To the untrained eye all would be equal, but not to your expert skillfull, gaze. You notice a difference in the quantity of nutrient used this time. A little less? The level of the remaining liquid somewhat above where it would normally be at this step of the operation.

How could this be? You did everything by the book, YOUR BOOK! Everything done as it has always been done. You gasp, thoughts racing, "how can it be!!!"

You dash to the car, hoping to catch your vendor before he leaves for the day. You have to get to the bottom of the mystery. You arrive while the salesman is still there, much to your relief. Your eyes meet, he sees the concern in your face. You explain the problems. He begins to check the meter, looks in his book, and slowly a smile starts to form on his face. "Say there sir, did you want to buy a 0.5 conversion unit or a 0.7 factor unit? Your reply, "HUH?" "Oh, sorry, there must have been some confusion when we served you earlier, we gave you a different meter." "Ah, Hah," you beam with pride and sigh with relief, knowing that it was not you who had erred. What does this little scene tell you? Small increments of difference, less nutrients, lower yields by accident, less money in the bank long term. All avoidable if we were working with just one scale, the EC scale.

So I have to ask once again, why would anyone want to work with different forms of measurement, more complicated forms of measurement, and on top of that, two undeeded and misunderstood factors of conversion. Especially when there exists one extremely precise, easy to use, hassle free form of measurement with no factors of conversion.

Yes folks, I do want to convert you all to this effortless, painless, simple method of doing your nutrient measurements for your daily operations. I want to make a difference to your growing experience, make it more enjoyable, less frustrating, and more profitable. I believe that you want this too.

So I am encouraging you all, come on down to the new age of measuring nutrients. Come on down to the world of EC and remember: To EC or not to EC, Only one choice, EC is the only way to fly!