Ph dropping week 3 bloom. please help!

[NovaPilot]

hello. I'm currently in week 3 bloom and running an 8xl current culture rdwc set up for the first time. I am experiencing a slow but steady ph drop. After doing a full nutrient change out with my ec/ppm on the money and a ph of 5.8 my ph dropped to 5.2 within the next 2-3 days. I then did another full nutrient change out and the same thing is happening with my ph now down to 4.9.
Once again my ppm's started out on the money and have only dropped slightly. Also my roots are perfectly white and everything is very clean. Please help!!

 

[Growrx]

Are the plants drinking a lot of water?
What nutrients are you using?
Is your ppm rising?

I experience this same issues, but what I do is check it daily, then wait till it drops to around 5.5 ( which might be too low) but that’s when I catch it, and bring it back up through my external res to 6.5 and let it slowly drift down again. Try setting the ph a little higher near 6.3 When you first make your mix. You should also keep an eye on the ppm it might be slightly rising due to the plants possibly taking up more water than nutes.

 

[NovaPilot]

hello and thanks for they reply.
im using cultured solutions nutrients by current culture. i'm following their schedule exactly.
Since the ph has been dropping (this hasn't happen before) the plants do not seem to be drinking as much water and the ec/ppm has stayed the same.
I have been setting the ph at 5.7 because up till now my ph has always risen during the week. Also, current culture told me i should not be using ph up at all, my ph should be rising during the week which it always has until now.
I just added ph up instead of doing another nutrient change out. I'm at 6.2 and holding steady for a few hours now. the plants look beautiful, ill keep you posted.

 

[Growrx]

How have things been going bud?

 

[Aqua Man]

Ok can you link all nutrients and any additives you are using?
Source water including ppm and ph?
Pics of the plants and the roots?

This is not that uncommon to see in mid flower but it CAN be a indicator or root issues of system issues.

What exactly is the EC/PPM you are running and how much is it changing daily?

If things are healthy then it just needs managed and I can help with that. It may be as simple as slightly more alkalinity and PHing a bit higher than normal. Or it could be a bacteria bloom, root rot or other.

 

[NovaPilot]

Once I bumped the ph up using "ph up" it stayed exactly at 6.2 for the remainder of the week. The only reason I was hesitant to use ph up is because the tech support at current culture told me I shouldn't be using "ph up" at all... So I'm into week 4 of bloom now, I did a full nutrient change out and everything is holding steady right where it should be. Roots are looking nice and white. Im using Current Culture's Cultured Solutions and i'm following their shcedule exatcly. My source water is r.o. filtered and starts off with a very low ppm and is at zero after being filtered. So at the moment everything looks good, thanks again for the input!!!

 

[Aqua Man]

Once I bumped the ph up using "ph up" it stayed exactly at 6.2 for the remainder of the week. The only reason I was hesitant to use ph up is because the tech support at current culture told me I shouldn't be using "ph up" at all... So I'm into week 4 of bloom now, I did a full nutrient change out and everything is holding steady right where it should be. Roots are looking nice and white. Im using Current Culture's Cultured Solutions and i'm following their shcedule exatcly. My source water is r.o. filtered and starts off with a very low ppm and is at zero after being filtered. So at the moment everything looks good, thanks again for the input!!!

I never understood why they say that. The ph up adds alkalinity to the water increasing the buffering capacity and while it may take a bit more acid to adjust it results ina much more stable PH.

 

[NovaPilot]

When I first started the RDWC system I had no previous experience, although I was studying youtube videos for about a year. So when I first nutrified my water and then ph'd it I was shooting for the target ph provided by current cultures comprehensive graph. I started off kind of high at 6.3 thinking if it was too high I would simply add ph down. What I didn't realize and was not told is that my ph should be rising during the week and I should have started my week off on the lower end of the spectrum, around 5.8. I ended up fighting the ph and had a problem, that's when I contacted current culture for help. So as long as the ph only rises and never drops Current Culture's advise makes sense.. but like I said, I only added a small amount of ph up and it worked perfectly. It's definitely a learning experience... thanks again for the input i'm learning a lot from everyone on the site!

 

[overfeederr]

I had the same issues RDWC with tap water and then RO water. It seems to be more stable with lower EC from 1.8 to 1.2 over few grows. But after using RO for 2 cycles I think I was adding too much CAL-MAG to the RO water. I don't think it needs to be higher than 0.2 at any point(or even less since there is CalMag in my nuts) but I was always making it up with cal-mag up to 0.4 before adding anything else.

 

[overfeederr]

Also had another issue with Tap water, when topping up water in the system pH would shoot up. RO water seems did not do that it would mix together without pH change. In general EC of tap water here is 0.4 . Would be nice if you share your further results.