I also use a “pulse watering” method. Similar to what you described, ill use a 20 oz. water bottle and sprinkle a bit on each plant. Then I refill and repeat. Usually watering 6-10 plants this way. If I was doing a larger grow, I don’t know if I could do it that way. I also avoid run-off, measuring water volume and weighing the pots (just by hand) to judge how much water they need.
Lots of ways to skin a cat.
Right I water my plants with 15 litres of water (5 galons) every two days. Everytime I fill up my 1,5 litre bottle with solution and water one plant per bottle as quick as I can 
The water runs throug the coco and I can hear the oxygen sizl on top of the medium 
I have always 30% runoff this method (my pots are 1 galon) then I measure my pH and Ec. I can clearly see my salt build up I always water with Ec 1800 - 1900 pH 5.9. And my salts go like this: 2200 - 2330 - 2500 - 2600 and 3150 two days ago. But my pH goes like this: 6,1 - 6,1 - 6,0 - 5,8 and 5,7 last time.
So…I have a question Do you think I should flush? I am in 5th week flowering. Last time I flushed was exactly 2 weeks ago when my Ec was 3200 and it went to 2000 beacause of the flush Please help The plants are looking absolutly beatiful and super healthy and no there is no sign of overfeeding what so ever. But I am a bit worried about he high Ec. What do you think?
I’m an organic guy, I’ve never flushed a plant in my life. I’ve occasionally measured pH or EC.
@Fisch, that Ec looks kinda high imho, I’d probably flush em. Are the salts bonding to the Coco? Like you, I try to feed mine between 1800 - 2000, pH 6.2, but I’m still learning. How many plants are you growing? I alternate feeding or watering every other day about 2.5 litres per plant in 5 gallon dirt pots. I don’t get any run-off to test unless I give > 6 litres. I think the soil (no Coco) & dirt pots absorb it all. I’ll do another soil test for Ec when I find time, (holidays ya know).
I’ll be going organic as soon as I use up all the chemicals I have.
Allowing water to run from container plants allows the plant to flush toxins and salts that build up near the roots. Some plants are sensitive to these conditions and the roots will sour.
What salts? No-till bed gets zero run-off. The ROLS containers get as little as possible (usually a quart of runoff from 8 plants).
Then your roots would only be exposed to that which is left over. Shouldn’t be an issue.
I learned that about 10% of total water volume in runoff is more than enough.
These would form when nutrients (usually man made) break down.
Yes, I was being a smart ass. I don’t use salt based nutrients. Maybe I should add some sea salt to my water.
Good choice.
Sea Weed!
Hoping everyone’s holiday season was good. Mine was busy, but enjoyable. Now it’s time to get back to …
A few pics of the girls. The stretch is over now & the girls are filling out. Lots of Trichomes developing.
Well, another week has passed and plans for the next grow (@LED_Seedz Strawberry Cream) are finalized. Nothing to do but, hurry up & wait. So I took a few pics today.
I had a good Q&A session with my local mentor the other day. He insists I use EC only and ignore tds readings to avoid under feeding. He pushes his plants a bit, 10-15% higher EC than I’m used to reading about. Any thoughts?
Total Dissolved Solids (TDS) is the best measurement of the nutrient concentration of a hydroponic solution. To estimate TDS, one can use a meter that measures the Electric Conductivity (EC) of a solution, and convert the number to TDS in parts per million (ppm). Many meters will do this conversion.
Total dissolved solids (TDS) is typically expressed in parts per million (ppm). It is a measurement of mass and determined by weighing, called a gravimetric analysis. A solution of nutrients dissolved in water at a strength of 700 ppm means that there are 700 milligrams if dissolved solids present for every liter of water. To accurately calculate total dissolved solids (TDS), one would evaporate a measured filtered sample to dryness, and weigh the residue. This type of measurement requires accurate liquid measurement, glassware, a drying oven, and a milligram balance. Example: 50 mL of the 700ppm solution would leave 35 mg of salt at the bottom of a crucible after drying.
Electrical Conductivity (EC) is expressed in siemens per centimeter (s/cm) or milliseimens per centimeter(ms/cm). It can be determined with an inexpensive hand held meter. Nutrient ions have an electrical charge, a whole number, usually a positive or negative 1, 2, or 3. EC is a measurement of all those charges in the solution that conduct electricity. The greater the quantity of nutrient ions in a solution, the more electricity that will be conducted by that solution. A material has a conductance of one siemens if one ampere of electric current can pass through it per volt of electric potential. It is the reciprocal of the ohm, the standard unit of electrical resistance. A siemens is also called a mho (ohm backwards).
For convenience, EC measurements often are converted to TDS units (ppm) by the meter.
The meter cannot directly measure TDS as described above, and instead uses a linear conversion factor to calculate it. Everyone’s nutrient mix is different, so no factor will be exact. The meter uses an approximate conversion factor, because the exact composition of the mix is not known. Conversion factors range from .50 to .72, *depending on the meter manufacturer, which do a good job of approximating a TDS calculation from the meter’s measurement of EC.
EC is measured in millisiemens per centimeter (ms/cm) or microsiemens per centimeter (us/cm).
One millisiemen = 1000 microsiemens.
EC and CF (Conductivity Factor) are easily converted between each other.
1 ms/cm = 10 CF
“The communication problem”…
So again, the problem is that different ppm pen manufacturers use different conversion factors to calculate the ppm they display. All ppm (TDS, Total Dissolved Solids) pens actually measure in EC or CF and run a conversion program to display the reading in ppm’s.
There are three conversion factors which various manufacturers use for displaying ppm’s…
USA 1 ms/cm (EC 1.0 or CF 10) = 500 ppm
European 1 ms/cm (EC 1.0 or CF 10) = 640 ppm
Australian 1 ms/cm (EC 1.0 or CF 10) = 700 ppm
For example,
Hanna, Milwaukee 1 ms/cm (EC 1.0 or CF 10) = 500 ppm
Eutech 1 ms/cm (EC 1.0 or CF 10) = 640 ppm
Truncheon 1 ms/cm (EC 1.0 or CF 10) = 700 ppm
Calculating the conversion factor
If your meter allows you to switch between EC and TDS units, your conversion factor can be easily determined by dividing one by the other.
Place the probe in the solution and read TDS in ppm. Change to EC on the meter and read EC in ms/cm.
Conversion factor = ppm / ec.
[Note: ms must be converted to us: One millisiemen = 1000 microsiemens (1.0 ms/cm = 1000.0 us/cm)
According to the chart below:
1.0 ms/cm = 500 ppm (USA Hanna)
1000 us/cm = 500 ppm
Conversion factor = ppm / (ms/cm * 1000)
.50 = 500ppm / (1000us/cm) ]
The answer is your meter’s convertion factor and should be a number between 0.50 and 0.72 To improve accuracy, take ec and ppm readings from your res daily for about ten days. Average the conversion factors. The more data points that you use, the closer you will be to finding your true conversion factor.
When reporting your PPM in a thread, please give the conversion factor your meter uses. For example: 550 PPM @0.7 or give the reading in EC, which should be the same meter to meter.
It may also be advisable to give the starting value of your water; there is a huge difference between RO and distilled water with a PPM of approximately 0 and hard tap water of PPM 300 @.5 (notice the conversion factor so others can work out the EC) or well water with a conductance of 2.1 ms/cm.
A note to Organic Growers:
An EC meter has fewer applications for a soil grower because many organic nutrients are not electrically charged or are inert. Things like Superthrive or Fish Emulsion, blood meal, rock phosphate or green sand cannot be measured with a meter reliably when they are applied or in runoff. Meters can only measure electrically charged salts in solution.
“The solution”…
When reporting your PPM in a thread please give the conversion factor your meter uses for example 550 PPM @.7 or give the reading in EC (the EC shoul d be the same meter to meter).
Thanks for the very thorough explanation @LED_Seedz. I think you, and my crusty, old-timer mentor are somewhat in agreement
He just chooses to ignore tds. I think my reference materials show a max EC of 1.8 ms/cm in wk 6, while he suggests 2.0 - 2.3. It’s a little late in this grow to start changing things. What do you consider a “moderate” nutrient level for Strawberry Cream?
That entirely depends on the type of food you are using. She is very indica dom, can eat quite well and is a very dark plant by nature.
I honestly don’t see many plants that need to go much above 1.6 [with GH nutrients] to do well in full tilt flower production. Anyone that’s going to suggest using numbers that high is not reading the plants, and just going from what they read or have seen on a specific strain. There are certainly some exceptions, but that is not the rule.
I’d venture to guess that your mentor will also suggest a flush at the end which if feed correctly just isn’t needed.
Looking at your pics, I would say you have your plants right where you want them. Zero to little tip burn which is an indicator, and green on top as they are on the bottom.
If you show slight yellowing near the bottom you feed a little bit more. Little tip burn sets in, little less. In other words, let your plants tell you how much they want to eat and stay proactive and not reactive if an issue starts to rise.
I would leach i wouldnt flush with plain water i would make a solution prolly about half of the solution you want it to be to even it out you can cause osmotic chlorisis if you flush with just plain water but like @LED_Seedz said if your plants are reading good i wouldnt really touch it
Thank you for that encouraging opinion of my plants. The first 3 wks. after the flip were very problematic. Thanks to the OG Community, I was able to get them healthy again. I agree with you 100% on the EC levels and being proactive.
As for my “Crusty Mentor”… he’s one of those exceptions. I don’t stand a chance debating a guy who’s been growing for almost 50 yrs. (he doesn’t handle dissent well). Every time I see his grows, I am literally awestruck. Can’t argue with success.
I’ll be popping the all those SC beans in 2 weeks. Diary to follow.
It’s been a busy week for me but, not so much in the tent. The girls are fattening up nicely, trichs are still clear, with about 15% amber pistils overall. For some unknown reason, this run is about 7-10 days behind my first Borderliner grow. Well, On to the picture show…
I plan on flushing them in about 5 days. I flushed too late, for it to be effective, last run.
where is the borderliner from? i’ve heard lots of good things i think about that… or am i thinking of shoreline? idk it looks juicy as shit tho
i think EC is best measurement because 1 EC will always equal 1 EC, TDS/PPM meters are just measuring EC and converting and the conversion depends on which salt it’s compensating for. here’s a list of which manufacturers use which
The ppm 700 scale is based on measuring the KCl or potassium chloride content of a solution. The ppm 500 is based on measuring the NaCl or sodium chloride content of a solution and is also referred to as TDS - total dissolved solids
Greetings @legalcanada and thanks for the Nute info. It never occurred to me that nutrient mfrs. used different tds/ppm calibrations in their feeding recommendations. That may be partly to blame for my deficiencies this grow. I agree… EC is EC (I’m easily confused).
I got the Borderliner XTRM (fem) from Amsterdam MJ Seeds. I really like this strain, but I too, would like to know it’s genetics. The gear came labeled “F-10” (the freebies were F-5’s) what ever that is. I was a newb & bought it based on the hype. The cured bud smells medium dank, not overpowering, earthy, mild mint/grassy spicy undertones. Great buzz & good for pain relief too. Flushed them yesterday… Won’t be long now 
