Beginner grower in dwc




What strain, Seed bank, or bag seed (photo or auto) ILGM blue dream photo seeds
-Age of plant 3 weeks one in hydro system
-Method: Soil w/salt, Organic soil, Hydroponics, Aquaponics, KNF… Hydro
-Vessels: Type and capacity of container (fabric, plastic, etc) four 5 gallon plastic container and res.
-PH and TDS of Water, Solution, runoff (if Applicable) as of last testing ph 6.3 gradually increases .2 ph every day it appears
-PPM/TDS or EC of nutrient solution if applicable ppm was at 660
-Method used to measure PH and TDS…digital tester
-Indoor or Outdoor if indoor, size of grow space… indoor 4x4x8
-Light system List brand and wattage/spectrum… ac infinity full spectrum
-Actual wattage draw of lights… 400 watts
-Current Light Schedule…18/6
-Temps; Day, Night usually around 80 to 90
-Humidity; Day, Night stays around 25 to 30 but i mist the plants regularly until humidifier comes in
-Ventilation system; Yes, No, Size not sure only have the in line fan
-AC, Humidifier, De-humidifier,… humidifier in a couple weeks
-Co2; Yes, No… yes but haven’t used it yet

If growing Hydro some additional questions:

-DWC? RDWC? Autopots? Ebb and Flow? Other? Dwc
-Distance of liquid below net pot (DWC) …about 1 inch
-Temperature of reservoir… chiller keeps it around 70
-TDS of nutrient solution…na
-Amount of air to solution…na

I’m wondering if i should be concerned of the brownish color coming from my roots. I use fox farms and had to adjust ph twice in one week by using sulfuric acid mixed with distilled water. I assume it’s time top of my nutes since it’s been about a week and i wonder if the brownish is coming from the water also needing to be replaced. I’m new to growing at every phase and not sure if i should replace water with every nute feeding according. I know the fox farm schedule says to flush water after sledge hammer but not sure from there. Other question i had was since my ph raises each day should i top off with nutes once it hits like 6.5 let’s say to drop it down or should i use ph down instead?



I cleaned the roots by splashing water at them and the brownish color came off. I wonder if it was due to this build up which i think might be the nutes i am using fox farm big bloom. See pic. I wonder if my pump is not circulating the water properly? Or is this something else besides the nutes sitting around

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That looks like root rot. Do you use anything like hydrogen peroxide or Hydroguard?


I don’t but i just bought some hydroguard and should arrive today. Should i flush my system? I possibly made the mistake of topping off my nutes yesterday. I cleaned them off with hydrogen peroxide and it seemed to help. Sorry for late reply i wasn’t allowed to reply due to maximum amount reached for a new account.


It would probably be best to clean your reservoir and start fresh with nutrient and a preventative. Ph around 5.5-5.6? Let it climb up.
I know that can be a pain…
I hope someone else here has some insight it’s been 8-10 years since iv done hydro…but I’m here to help if you need. Just tag me.

Thank you i appreciate the feedback. I thought that would be the best way to go as well. When cleaning the res should i do it when the lights are on or off?

I don’t see any issue with either? As long as you keep the roots protected and out of the light for an extended period.
Maybe mix up some hydrogen peroxide and water solution with a wash cloth to wipe the insides of the buckets to disinfect anything that might be lurking.

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@Autos-only @TDebWilly i did a complete res change cleaned all buckets with hydrogen prroxide and distelled water. Added the recommended amount of hydroguard. Waited a day didn’t see anything change. I decided to add more hydroguard and still have yet to see any change. The tent smell mushy not sure if it’s the nutes or root rot. My water temp in res is always below 70 i have a water chiller and tent temp is around 80 to 90. Any more would suggestions would be appreciated. Here’s some pics of one of my plants that seems to be affected the most and one that appears to have the same roots just not as bad looking.

RDWC/CO2 grower here.

Your plant looks fine. I suspect your nutes have a bit of a brown tinge to them, and it’s depositing on the roots… I haven’t used Fox Farms nutes, so maybe that’s not it.

Definitely add Hydroguard 2ml/gal as the last thing (after final pH of res). Inexpensive (more or less) insurance.

You’re going to need a dehumidifier much more than a humidifier; you only need to humidify when the plants are small and you need to keep VPD low. Once the plants get big, they’ll evaporate a lot of water into the tent - hence, the dehumidifier.

If you turn on your CO2, make sure to keep an eye on VPD, temps, and nutes. With CO2, you can increase VPD, light, and air temps (keep the nutes low). I don’t think there’s any need to go >1000ppm CO2.

There’s differing opinions about CO2 in flower. I’m “pro”, but it’s tough to get enough light on the plants in 12/12 to take advantage of the increased CO2.


I think at this point I’ve added double the amount of hydroguard maybe i panicked. It’s hard for me to distinguish if it’s root rot or the nutes right now. I’m still in between. Here’s some pics of my roots before and after rinsing them off with some distelled water. My biggest concern is the smell i wonder if it’s normal and maybe my in line fan just needs to be running faster. Or if it is due to root rot. I think my roots have been like this for a couple days now and haven’t really seen many signs of failure except the droopyness in 2 plants not sure how long rot would take over.

The plant itself looks healthy i think

If that were my plant, I would use straight hydrogen peroxide from the drug store (I think it’s only 3%) and I would spray my roots until they were white again. I’ve also been known to cut off parts of roots that stayed brown and slimy.

I did that and they get white pretty fast but then within an hour are pretty brown again and stick together. It’s leading me to believe it is the nutes but then again my water is not looking as brown as before. I do notice some brown stuff sticks to the container so it’s contradicting. At this point i so believe something is going on because my leafs are starting to turn yellowish from the bottom end leaves and i noticed this in my net pot can someone tell me if it’s normal

@Jungle i think i took care of the root problem but now I’m experiencing brown spots and different symptoms on my plants. I suspect it to be nutrient burn but having a hard time distinguishing between that or nutrient deficiency. My ppm started at around 700 and ec at around 1600 and they both climbed up about 150 each within a couple days and stayed the same through out. I did top off the reservoir with about an extra gallon of water and not much change.

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Eh? Your EC can’t be 1600. Do you mean 1.6?

Maybe I’m making it up, but I don’t think you can really overfeed DWC.

Your PPM is on which scale? 500 or 700?

1600 would be 800ppm? Maybe drop that to 700? How are you ph swings?

My meter shows it in both forms from what i can tell but yea 1.6 when i first started the new reservoir and around 650-700 ppm in 500 scale.
@Autos-only my ph swings daily usually from low to high so i have to add ph down every night. Right now my ec was around 1.8-1.9 and ppm around 850 to 900

That sounds about right, I would try to not let the swing get up to the 800-900 mark.

Maybe 600-750… 900 is really high and I haven’t heard of many people going higher than 850. Dwc doesn’t need as much.

I recently started to test my ph with the droplets instead of the ph pen and saw that they were not showing the same ph so i decided to buy some ph calibrator today and my ph pen was off about 1ph so every time i saw 6.8 it really was at 5.8 and by me dropping it it must have been out of range. I hope that solved my problem but i will still take your advise and drop my ppms. Last question i had was if my ppm starts at around 150 ppm should i still only increase it to the 600 to 750 orincrease it by the 150? Would i be better off using RO water?

The droplets are a good back up but I don’t recommend using them all the time, everyone sees colors differently.

Glad you got your ph pen figured out that’s a huge variance!
Ph is incredibly important with hydro.

I would still run in the 600-700 range counting your tap and see how that
runs, if they ask for more give more but with DWC everything is available for the plant and if ppm drops significantly day to day just up it a little.

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@Jungle @Autos-only I really appreciate the help. Last question i have. I’m having a hard time understanding the feeding schedule. From what i read everything contradicts each order when it comes to changing reservoir. From my understanding i have to change the nutrients in my system after each week and in the process i would assume the water as well? I mean how else would i keep my ppm under the 800. Yet i read that a lot of growers go weeks before changing reservoir which i would assume just requires topping off during that process with more nutes. What are your takes on that. Would i benefit from changing the water each week with new nutes or just topping off as i go?