So i just started a rdwc grow for the first time, so i’m new to this. I have a question about tds readings, check in reservoir and there 624 and take a reading from the return and it’s 1040 what’s up with that?
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Could it be residue from your clay pebbles??
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Like i said i’m new to hydro! Experienced dirt grower but same rules don’t apply i guess. Need some help!!
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morning @jdw …the TDS value in your reservoir and in your buckets should basically be the same…if you just put the system together it could be as @LateNightGardner said some settling in of the system components but that should only be for the first 24 hours after that all should be settled in…
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It’s been up and running for 17 days. Got me stumped. Thanks for the quick response.
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do you have a picture of your grow setup…maybe I can see something
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Lights are off right now but i’ll get back to you later, Thank you.
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Did you rinse your hydo pebbles before you added them to your buckets? I had pebble dust in my buckets even though I had done an initial rinse when I first used them.
Or, if your plants are using more water than nutrients that can cause your ppm to rise due the reduction of water and not as much uptake in nutrients.
Or a combination of both of these scenarios. Plants drinking more more than nutrients and some dust from your pebbles.
That’s a classic sign that your environment is hot and plants are thirsty. They drink are drinking water but aren’t taking up nutrients.
In this case you should check; pH and make sure the pH isn’t out of wack cause nutrient lockout. Temperature of your tent, between 85F - 65F.
The difference in TDS (Total Dissolved Solids) readings between your reservoir and the return could be due to several factors. In a recirculating deep water culture (RDWC) system, the TDS meter measures the concentration of dissolved substances in your water. It’s possible that the return water has a higher concentration of nutrients due to uptake by the plants or evaporation which concentrates the solution.
I did rinse my pebbles several times and there was a lot of red residue in the bottom of the totes. Changed the reservoir day before yesterday, things seem to be getting better. Put pH at5.8 and TDS at around 750, I’ll give that a try. Thanks very much for the reply!
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Check your roots for slime. You’ll also find out on your air stones.
If you have the white slime there is only one way to get rid of it.
Soaking in bleach doesn’t work
Soaking in h2o2 doesn’t work.
Mixing them both doesn’t work
Hydrogaurd doesn’t work.
Beneficial bacterial tea does work.
I had these same problems work my last (first) hydro grow and the tea made life wonderful.
3 gallons water
30 ml molasses
30 ml southern ag garden friendly fungicide
15 ml dynomyco Premium Mycorrhizal Inoculant
Mix well. Add an air stone and wait 24 hours. A bubbly foam on top is good.
Initially add 1 gallon at reservoir change and 1 cup daily. Tea last about 7 days.
I use this my entire grow and no problems.
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Yes i remember when you were having problems. Do you know what cause’s this condition? I’ll give your solution a try.
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That’s good news. Check your daytime temperature and humidity. Plants can be needing water due to heat/humidity. It’s normal for evaporation and/or respiration to be depleting the water content. This would leaving behind unused nutrients in your buckets.
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Temperature lig.hts 73 off 67. Thanks
I just thought of something.
How are you reading the two? Dipping reservoir? Are the air stones in the reservoir?
I recommend using a solo cup. Dip some out of the reservoir and take your reading. Dump it back in and fill it with water from the return.
Moving water and air bubbles can throw off the readings.
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Tried that, that’s where the readings differ. That’s what had me concerned. What reading should I go by?
They should be almost the same.
Please post some pics of the system.
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Finally got pictures posted
That’s a ton of bubbles. Maybe it’s a crazy thought, but try turning off the air stones for 15 minutes. Leave the system running and then check the water.
I think that’s from silica, I’m using power si when I mix it does the same thing. But I’ll try cutting down the air a little. Thanks for the help!