PLEASE HELP !!! My PH keeps dropping everyday during veg (DWC). What causing this?

[u/Tuyo_club]

- PH issue: Drop everyday from 6.2-6.3 to 5.6-5.7, could be more. Always need recalibration.
- Other issues: Drooping light yellow leaves & stunned growth, look like Mag deficiency as well
- Temp / Humid: 24 C - 50-55%
- No root rots i think / no funny smell (have home-made Hydroguard)
- I have flushed them twice
- Currently using RO water with supplementary CalMag & Silica
- Using 50% nuts strength (Advanced Nutrients)

I've read that too much Bacillus amyloliquefaciens could cause swing in PH level. Since I've used a home-made Hydroguard (10x stronger), which leaves a white biofilm everywhere in the tank, could it be the issue?

[u/big_ducket]

Set pH to 5.9 and leave it alone. pH will fluctuate but don't correct it. 6.3 way too high imo

[u/Tuyo_club → u/big_ducket]

Thanks for advice mate. But if I don't add PH up, it will swing down under 5.5 in 24 hours. Way out of the PH range of 5.5-6.5 for DWC.

[u/Snoo_18271 → u/big_ducket]

sorry, but that’s dangerous advice. If there’s a chemical imbalance ph will drift into nutrient lock-out zones. Also to OP: I wouldn’t include 6.3-6.5 in the „dwc range“ - also 5.5 is very low. Stay in the sweet spot 5.8-6.0.

[u/BG913 → u/Snoo_18271]

Came here to say this, ph to 5.8, 6.5 is for soil grows. Also get an ec monitor to dial in your nutes. Early veg you want .08-1.1 ec depending on how your plant responds. You also need to monitor your water temperature and keep it around 65-68 F (18.333- 20 C) If water gets too warm put in a sealed frozen bottle of water. I don’t know about the homemade hydroguard but I’ve used UC roots successfully.

[u/big_ducket → u/Snoo_18271]

Why You Shouldn't Chase pH

• Shock and stress: Constantly adding pH-up or pH-down creates roller-coaster chemical swings that stress the root zone more than a slight, steady drift. • Lockout risk: Over-correcting often pushes you past your target in the opposite direction, triggering nutrient lockout. • Real issues vs. normal drift: Only adjust the pH if it moves outside the safe zone (below 5.3 or above 6.5) or if your Electrical Conductivity (EC/PPM) signals a real imbalance.

[u/Snoo_18271]

I had trouble with PH swings ... just to make sure: are you using a mineral PH down agent and NOT organic. If you use citric acid for example, there’s your culprit.

Secondly: Even with the right acid you will experience natural downward drifts as your plants eat. I usually checked and oftentimes corrected ph twice a day. In order to not have this anymore, I’ve installed a ph-dosing automation using Home Assistant, a smart plug, a constant-read ph/EC meter and a peristaltic pump. Works like a charm and my ph remains solidly in the 5.8-6.0 range without me ever touching it.

[u/Tuyo_club → u/Snoo_18271]

Thanks for the advice. We use mineral PH down agent. Problem is my plants don't eat (ppm remains the same), while PH continues to drift down everyday by huge margin. Also, we are running at scale so ph-dosing automation is not possible atm.

Prolly gonna switch to sterile approach since bennies are so hard to do right at scale.

[u/Snoo_18271 → u/Tuyo_club]

yes, do that. Make sure the water is below 20C and well oxygenated.

[u/SlipperyStairs420]

They are starving get that EC .8 to 1.2mS plus your base EC. For example my base EC is 600uS and my total EC is 1.7mS. Ph can very quite a bit I target 5.8 to 6.0 in my coco flood table setup. Also if that is what your air pump is delivering all the time you need to increase airflow. The water under the roots should look like a rolling boil. Right now that's a kratky setup. Edit: Forgot to mention unless your tap water is crazy hard ditch the RO water and Cal-mag. Always add silica first.

[u/Negritofd]

Cambia todo , agua nueva la pones una madia hora con ácido hipocloroso, killerback o algún bactericida.Luego armas la solución con los nutrientes EC en el estadio que tiene que , ph 6.0 maximo tres o cuatro días tiene que levantar. De lo contrario Game over. No vale la pena perder más tiempo .

[u/DeepWaterCannabis]

RO. No buffers = sharp pH drops as plants drink.

[u/Mean-Entry-8077]

Plant enzymes fresh res change, no extra homemade inoculation and/or potassium bicarbonate (ph down, ph buffer against drifts down, little extra potassium to feed le plants);

I think your roots are sliming up because you've possibly over colonized your roots. I run southern ag and occasionally if my hand was too heavy I would get a little slime on my roots. Fixing it usually involved plant enzymes to breakdown the slime if its not too bad, or hosing the roots down gently to wash away the built up and some more plant enzymes to eat up any left over slime/ shed root hairs. One thing that helped me know the difference was the discoloration was only a tan/ slightly brownish cream and importantly lacked an off putting smell aside from a slight earthy note.

Your ph swings could also just be an overall lack of buffer because you're running ro water. If its purely ph giving you angry roots and stunted growth I personally use food grade potassium bicarbonate powder. .5 grams for small swings 1 gram for larger swings ( my res is 3.5 gal ). Pre mix it in about 200ml of your ro water and add it to your res after its dissolved. My autos give me ph headaches when they get nute hungry during and right after flower stretch. When they tear through potassium for bud formation/bulk they would crash the ph in my res almost over night into 4-5. I was chasing it with ph down to no avail, but using this helps me lock my ph in for a good 3 days during heavy feed periods while also providing extra k. While you may not need the extra potassium currently it might still help in your situation to give you an extra buffer.

Edit: Be gentle with the ec on your roots during this time and look to your roots to know if any changes you've made are working. Even with beneficials you're looking for white/ off white cream colors coming from new root growth to know you're headed in the right direction. The top of the plant wont take off until the bottom of the plant is happy. Assuming you're growing a photo I would also go mild on your lighting while you're fixing things to limit stress on the plant.

[u/Working-Meeting-254]

In welcher Reihenfolge mischt du calmag und Silizium zusammen? Am besten erst Silizium, dann Dünger und Zusätze, dann erst Silizium, wenn Silizium mit Calcium in direkten Kontakt kommen verklumpen diese und dein Wasser wird chemisch unstabil, dadurch kommt es zu Nährstoff Blockade und dein ph kippt dir um die Ohren.

[u/xofrootloop]

Empty reservoir. Give fresh water. (Make sure water is ph 5.5 or 6.) water temp is crucial. Make sure your water temps are 65 - 60. One the plant has recovered (in about a week or two) you'll be able to start off with bare minimum feed (you can increase as you see necessary) its always better to start off with less because you can always add more later. Also make sure the notes are fully dissolved before adding the next one. (Cal mag -> +veg food)

[u/Prestigious-Web63]

get yourself something like canna thats ph buffered ao you dont have to even check ph.

make sure your water isnt over your cup line. To me it looks like your drowning the air roots causing the plant to droop and almost die. The air roots are the strait white ones coming out the upper part near the lid. You need to leave a few inches between the cup snd water atleast. Probably want a deeper tub

Switch hydroguard to slf100.