Tds reading on run off of plant

My plant isnt showing any real issues but i just took a run off reading of 3.6 ppt on my apera ph meter. Running ocean forest soil that I recently re-amended after a ill advised flush. Im guessing i should be expecting some serious issues in my future?

If your meter is giving you ppt instead of ppm then that is an extremely low reading. Are you sure that meter is working right? If it is then when and what do you amend with?

So that reading was off of about 10% run off on todays watering. Thats Earth dust mostly base abd some bloom. With recharge and cal-mag the only other things added

What reading does your meter give you in tap water?

My tap water without anything added is running 6.9 range ph and tds reading 55 ppm range

Salts .04

Question is does the amount of runoff give you scewed numbers if not enough?

That’s strange. I punched it in a converter bc I no longer do math and it said 3.6 ppt is 0.0000036 ppm. That’s extremely low. But 5.12 EC is high. That’s 5120 microseimens. Maybe I’m making an ass of myself because I’ve never used that type of meter. I use apera for pH and a cheap TDS meter. This is where I tap out and get you some help.
@OGIncognito @Graysin @Storm @beardless @MidwestGuy @Docnraq


That’s what I thought. How can the runoff be lower TDS than tap water? If the runoff EC is 5120 I’d expect it to be around 2600 ppm. Maybe just a faulty reading. I’m not sure what the runoff numbers should be for amended soil, but I know it’s not 3 ppt. I have no idea what’s going on but one of the people I tagged should be able to provide guidance for you.

Welcome to my clueless quandry that has me scratching my head ill recalibrate my pen.

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I think you want runoff 1000-3000 ppm with amended soil, but don’t hold me to that. For some reason amended soil throws me off. Wait for backup.

Thanks for the help outlaw, im flying by the seat of my pants still being my second grow. First photoperiod run.

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I’ve been growing in the woods for 30 years, but I’m currently finishing my second indoor grow. Got a good grasp on most aspects of growing. But when it comes ro amended soil and dry amendments I’m basically clueless. At least your growing photoperiod plants so if you do mess up there’s time to correct the issues.

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Appreciate the tag Grow Bro and I’m not familiar with the Apera PC60, I use the Apera 20 and a blue lab TDS pen. Did some quick research and seems I need some time to read and digest the info researched…not as simple as I thought :love_you_gesture:


If I recall, the ppt on the Apera is parts per thousand not parts per trillion. So it’s like 2560 PPMs(?) on the 500 scale.

That is high.

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Good snap to - I didn’t even see the Earth Dust. :100:

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Ok great ill settle for smaller watering. So for a organic soil in a 5 gallon pot how much water are you thinking per plant. Half gallon daily or every other in ideal environment?

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It depends on the plant. Likely water every 3 days or so. Been following this