Where should my TDS/PPM level be?

drdodge29

Well-Known Member
some people say their ppm levels are 1000 or under cause it'll mess ur plants up. Well I'm Using Dutch Master Gold Grow & Flower and my chart for PPM says at week 4 my PPM should be 1250, slowly rising to 1750 at week 7 for 3 weeks. Then drop it to 1100 PPM at week 11, and flush at week 12. Will those PPM hurt my plants or should I follow the instructions that my nutrient company tells me to follow?
 

Picasso345

Well-Known Member
I see no problem with those ppms. 1000 is no limit. In aeroponics we can get up around 2100 or 2200 ppms.
 

drdodge29

Well-Known Member
Yes and then adjust as needed.
Now Im confused...Wat conversion is Silky talking about? PPM is PPM right. Just like grams are grams. There's no gram that can weigh more than another gram. A measure is that if it's the same units. Can u explain Picasso? and when u say adjust as needed what do u mean? Are u saying if my PPM's are lower that what my nute company says, adjust my PPM? and how do I adjust my PPM? With my nutes?
 

Picasso345

Well-Known Member
Now Im confused...Wat conversion is Silky talking about? PPM is PPM right. Just like grams are grams. There's no gram that can weigh more than another gram. A measure is that if it's the same units. Can u explain Picasso? and when u say adjust as needed what do u mean? Are u saying if my PPM's are lower that what my nute company says, adjust my PPM? and how do I adjust my PPM? With my nutes?
Meters guess at the ppms. IMO, it has no relevance to this discussion though. What happens is the REAL number is something called EC (electrical conductivity) and meters convert that into ppms. Some meters guess at it a little differently. But that is nothing we need to worry about.

Here is what you do. Ppms are a measure of the nutes in your water. Start off using the nute mfgs instructions. If you see some nute burn, you back off the nutes a little - which means drop the ppms a bit.
 

TRICKKY

Well-Known Member
If you let me know what PPM meter you have I can probably tell you what the EC to PPM ratio is.

But as said above thats not really important.

Unless you have a Hanna meter.
Hannna ratio is EC(ms) 0.1 = PPM 50

So, a PPM of 1700 on a Hanna meter is an EC of 3.4 or CF of 34, which is a little high.

Most other meters have a higher PPM to EC ratio for example, my meters is EC(ms) 0.1 = PPM 70

So a PPM of 1700 on mine is only 2.5 EC. The difference between an EC of 2.5 and 3.4 is quite substantial and came be the difference between healthy or unhealthy plants.
 

drdodge29

Well-Known Member
Hey Picasso are u also Tricky????? And I have ordered a 3 in 1 digital meter, (CF/EC/TDS), so I should be good with that and I have also printed up a copy from my nute co.(Dutch Master) and it's in PPM and EC. It says when I'm at 1500 PPM, my EC shoul be at 3.5 does that sound about right converted. Also I'm growing in a bubbler 18 gallon rez. That shouldn't change my PPM's right. I still have to have that much PPM.
 

TRICKKY

Well-Known Member
Nope, We aren't the same person.

If you have a 3in1 meter and you have an EC chart, then follow the EC chart. EC is the more accurate and least confusing way to go.

EC is EC whatever pen you are using. PPM is a measurement your tester will estimate, using a set conversion scale.

If an EC(ms) of 3.5 was converted to 1500PPM then the conversion scale would be, 0.1 EC(ms) = 42 PPM.

Anyway, for ease and accuracy I would go with the EC measurement and disregard the PPM measurement.
 

TRICKKY

Well-Known Member
Also I'm growing in a bubbler 18 gallon rez. That shouldn't change my PPM's right. I still have to have that much PPM.
I can't answer that one sorry, I haven't grown in Bubblers before.

There are quite a few Bubbler growers here tho, who could give you some info on nutrient strength.
 
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