PPM questions

DiabloZoe

Member
I PPM my nutes and evrything else as I am in flowering to 1000-1200 and I use soil Im in 10 days of flowering, I check PPM run off and it was like 2300!!! Is this a viable check? Should I be worried? Do I need to check PPM runoff the same way you would check PH runoff?
 

DiabloZoe

Member
you check the same way you do with PH sorry for the lack of people wanting to help out :)
Thanks I understand that but how much different should be the PPM coming out? If PH is about the same when it comes out, is that all that matters? And no need to apologize just see post with 2500 replies thought i get some input!! But thanks for the reply
 

aknight3

Moderator
i check the runoff as well, honestly i dont check ppm anymore although i should, im focken lazy, but your soil does have some salts in it naturally to begin with and on top of that you do get nutrient salt buildup after awhile of feeding whether if be veg or flower, ppm just means parts per million nacl, doesnt exaclt tell you whats there, so you def buildup salts from previous feedings, i wouldnt worry to much about it as long as its green, growing well, and no bottom leaves are starting to yellow or look ill, if so id cut back on the nutes becuase that is high, but i think if you were going to burn them with it being that high i think you already would have, they must be tolerant to nutrients overall, hope this helps, pictures would tell another story.
 

hellraizer30

Rebel From The North
a run off of 2300 is high. to stop it from rising when I used to do soil was for every feeding the next time i watered it would be just strait water
so feed every other watering, helped keep that ppm run off number down
 

Snow Crash

Well-Known Member
PPM is based on a conversion from a measure electrical conductivity which is calibrated on a solution of NaCl. Different companies use different conversion factors to determine the PPM value shown. 1000ppm could represent anywhere from 1.5 to 2.0EC depending on the meter.

Bottom line though, a deviation of >100% of any value is bad news. 500ppm in and 1200ppm out would indicate the media contains a good deal of residual. In your case the build up does sound severe. 1000ppm to 1200ppm is far too high to feed consistently. Perhaps once during veg and twice during flowering, but not regularly.

I seriously suggest flushing the soil ASAP. You'll need to get your run off ppm under 700 at the least, I'm thinking about 3 gallons water per gallon of soil should suffice.

Take your feedings down to around 500 to 600 ppm and keep your run off levels over 25% and you shouldn't have this issue anymore. Let the organics do work and use more water.
 
Top