PPM Confusion

rydertr

Active Member
Hello all,

My last grow, I only used GHE Flora Series on and Atami Wilma dripper system with clay pebbles. I had a good yield, but now, after 7 years, I've set up a better system, using the same dripper but changed to Terra Aquatica TriPart Series (new brand for GHE), with additional supplements (Seaweed, CalMag, Fulvic Acid and TrikoLogic).

Any how, I have a few questions I need answers to, I hope you can help me.
1. What are the numbers on the nutrients mean? Micro 5-0-1, Grow 3-1-6 and Bloom 0-5-4. This numbers are used by most brands.
2. My feeding chart suggest ml/L of each nutrient and supplement. While they suggest an EC range for a stage of growth. When I add these nutes, I can never get the suggested EC, I always get higher than suggested.
3. The supplements also increase my EC level so at this point, I am confused. If I dilute the solution with more water, than the concentration will be lower than suggested. For example, at Growing stage, my recommended EC range is 1.3-1.8 (I am guessing with .5 conversion it is 650ppm to 900), but with the added supplements I hit 2.2 ms/cm EC which converts to 1100ppm).

I do not get nute burns on my plants. Although I am in week 5, I still have not seen any sign of sexing yet, but they are thriving at an adjusted ph of 5.8 from daily peak of 6.0. My humidity levels are fluctuating between 54% and 85%. The reservoir temp is at 25C (77F) and the tent air is at 28C (82.5F) when lights on. The tent is 80x80cm (32x32") with a height of 180cm (70"). I only used one pouch of bio CO2, which I do not know the level yet.

What is the correct way to approach the PPM/EC? My last and only previous experience, I never bothered with the PPM/EC. What do you suggest I do with these readings? I do not want to slow down my growth by diluting the solution nor want to stress the plants. Some say there is no standard for PPM/EC numbers and they change from plant to plant. If it is true, then what is all the commotion?
 

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Im in the same boat lol. always grew outdoors and my only concern was the PH level. My plants always did good despite my hard water . Im into my first indoor crop this year and took a ppm read of my tap water for the first time today and its 2200! I never drink my tap water. taste like the ocean lol but so far the plants are thriving . Doing a little research on on the topic but im considering going to a near by spring and stalking up on jugs of spring water
 

ColoradoHighGrower

Well-Known Member
Nice, thanks!
Just to add to this explanation, these three numbers offer information about the relative concentration or ratio of N-P-K concentrations of the product. I usually target an EC (electrical conductivity in units of mS/cm) of 0.9 or slightly more during flower. The ideal nute concentration is heavily dependent on grow technique, medium and strain of plant though. Best to start low and adjust as needed. The bottled nutrients products ALWAYS recommend way too much, so you use more of their product!

Don't overthink it: When you mix your various nutes together, simply add the desired ratios and then slowly dilute with water until you reach your target EC/ppm value. Easy peasy lemon squeezy! I go with cap-fulls per 5gal as a measurement approach with an EC meter and PH drops to ensure I'm on mark.
 

rydertr

Active Member
Just to add to this explanation, these three numbers offer information about the relative concentration or ratio of N-P-K concentrations of the product. I usually target an EC (electrical conductivity in units of mS/cm) of 0.9 or slightly more during flower. The ideal nute concentration is heavily dependent on grow technique, medium and strain of plant though. Best to start low and adjust as needed. The bottled nutrients products ALWAYS recommend way too much, so you use more of their product!

Don't overthink it: When you mix your various nutes together, simply add the desired ratios and then slowly dilute with water until you reach your target EC/ppm value. Easy peasy lemon squeezy! I go with cap-fulls per 5gal as a measurement approach with an EC meter and PH drops to ensure I'm on mark.
I am on the flowering stage day 2, ı am doing as you suggested diluting as needed. One quick question though, for the past few days, instead of increasing ph levels, I have steady declining ph level. Is this normal? I am upping it with ph+ to 6.0 and finding it 5.3-5.2 the next day. I use the same filtered water source from the start, so no change there...
 

Kaizen23

Member
You need to figure out what PPM your water is. You can "dilute" it with water all you want but if your water is 750 ppm you will never be able to hit 650 ppm WITH the added nutes. Simply impossible.

So get yourself a PPM meter and test your water. If your water has too many PPM, you should get an RO system. I have one called RO Buddie that is around $60 which I have hooked up to my garden hose. This will get you 0 PPM water and allow you to dial the nutes in.


I made a resevoir from a $10 storage bin from home depot. Just put a hole in the top of the bin for the line that puts out the good water. Attach the RO Buddie to the side of the bin. The bad water goes out via another line to the yard. That's it.

Also, here is the PPM meter I have:


And storage bin:

 
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rydertr

Active Member
What is declining in ph steadily? Runoff ph? Soil ph? How qre you measuring ph? What's your growing medium? Coco?
It is a recirculating system. So no runoff water, but the circulated reservoir ph level is dropping. I am using clay pebbles as I stated in my first post. I have Hanna probes for both ph and ec measurements. My current ec level is 2.0
 

rydertr

Active Member
You need to figure out what PPM your water is. You can "dilute" it with water all you want but if your water is 750 ppm you will never be able to hit 650 ppm WITH the added nutes. Simply impossible.

So get yourself a PPM meter and test your water. If your water has too many PPM, you should get an RO system. I have one called RO Buddie that is around $60 which I have hooked up to my garden hose. This will get you 0 PPM water and allow you to dial the nutes in.


I made a resevoir from a $10 storage bin from home depot. Just put a hole in the top of the bin for the line that puts out the good water. Attach the RO Buddie to the side of the bin. The bad water goes out via another line to the yard. That's it.

Also, here is the PPM meter I have:


And storage bin:

I do have the system set up for recirculating nutrition solution from a 30 liter reservoir. EC level is 2.0. Ph drops. Measurement products are by Hanna...
 
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