Nutrient burn/ overload help!

New grower here, looking for a little assistance…
Just at week 12 or dwc grow… however I’m a bit confused on ppm. From what I read it should be around 700-1000 at this stage… feeding fox farm hydro trio as recommended… cali magi, hydroguard, dechloronated water/distilled water. And following recommendations as per the schedule fed my system. However when I check the ppm after it was like 1700… so I started adding a few gallons of distilled water and got ph to 6… now my ppm shows 1011 but my plants look like death… everything is turning rusty brown.

What should I do? Complete h2O flush? Then go to half strength for a few days ? Leave it alone and see?

What bothers me is the directions on the bottle and schedule say ppm range should be like 1500-1800 but that seems way high no? And when I search here it seems like some hidden secret as to what ppm should be at each stage of growth.

What the best range of ppm during veg/flower?

Also how do you know you’re ready to flush and just leave them in h2O for the last two weeks? I understand I will need to monitor trichome turbidity (clear cloudy amber) etc to know when to harvest but how do I know I’m 2 weeks away?

Will add photos ASAP.

Thanks for any and all help everyone!

Auto flower Gorilla glue, critical purple, ak47
-Age of plant week 12 from sprout
-Method: DWC with 4 air stones
-Vessels: Plastic tote
-PH 6
-PPM of nutrient solution 1011
-Method used to measure PH and TDS - pH and ppm meters
-Indoor size of grow space 4 x 2

-Light system garbage blurple LED
-Actual wattage draw of lights not sure
Hlg 320xl on the way!

-Current Light Schedule 18 on 6 off - veg+bloom
-Temps; 70-72
-Humidity; 50%
-Ventilation system; Fans
-Co2; No
If growing Hydro some additional questions:
-Distance of liquid below net pot 2 inches with massive root balls in bath
-Temperature of reservoir 70
-TDS of nutrient solution 1011
-Amount of air to solution tons of air

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Probably a difference in scale of chart vs scale you’re measuring. 1000ppm is pretty reasonable number in dwc though. Always going to have situations where some plants may be a little sensitive and want 800-900 and others that want more like 1200ppm. Figure 800-1200 or so wouldn’t be ridiculous.

Ph of 6 isn’t terrible either, but try keeping around 5.8 in dwc. Let it float to 6 and then adjust back down. Also would keep a gap between solution level and bottom of net pot, but 2" may be a little more than needed. And 68f is ideal solution temp, 70 is doable.

I would like to see pics if possible, but I would guess that when you watered down you may have diluted calcium too much. Had similar issues when I tried fox farms, so I ditched it pretty quickly and don’t have a lot of experience with it.


Thanks for the reply, what nutrients do you use now?

He and I are using a JR Peters product called ‘Jack’s’ that uses dry ingredients: Part A, B and Epsom Salt. Same TDS and PH from seedling to harvest. There are a bunch of us using the program: Google Jack’s 3-2-1 and you’ll see a crap ton of posts. It’s also very economical.

Pictures are necessary to help diagnose but additional Q’s: roots are white/tan? Not slimy? No off smell in rez? How often are you changing out nutrient solution?

This is the downside of having a small working reservoir. As the plant takes up water/nutes it changes the solution concentration and volume very quickly. This means sometimes daily adjustment. (this is where R DWC is a distinct improvement over simple DWC)

First, Fox Farms is not in the business of conserving nutrients haha. Second; the grow schedule is based on the U.K. 700 scale and not the American 500 scale. Third, FF seems to run higher than other lines.

You will love the light and never look back. Save your blurples for starts and seedlings FYI.


If you’re a new grower you should also check out Mantis Buffered Nutrients. It’s a one part nutrient from seed to harvest. I haven’t experienced it in DWC but apparently it works wonders! It’s buffered too so don’t have to worry about PH as it keeps the PH in optimal range at all times. I haven’t grown a strain that hasn’t liked Mantis.

I love you guys and this forum!

pics inc.

Ok here are a few pics… plants look terrible

Roots are white not slimy but really massive some have formed these single roots that are as thick as a thumb. No off smell color is tanish or tea colored. Change them every ten days but it’s become super difficult changing totes with how big the plants and root systems have become, so from here out I’ll be draining by pump. How do I know when I’m ready to flush for the final time?

And just for clarification the second to last photo is of the GGlue which grew much slower and will have to be harvested later than the ak(I think).

Once you see pistils turn and recede it’s time to start looking at trichomes. Once you feel you have close to the ideal for you is the time to go to water only. You can also introduce a product like Flora Kleen or Sledgehammer to help remove salts from your grow.

Awesome thanks…

Sorry have another question… I have flushed my system completely today and have my plants in just water right now. How long till they start looking for nutrients after getting way overloaded. Can I let them chill in water for a few days or add nutrients right away?

Do they have hours?days?weeks? worth of reserves or do they start dying fast?

I ask cause I just ordered new nutrients and would love to wait for them to come in to be used without having to add more of what I’m currently using now.