Res pH jumped up .7 pt overnight! What's going on?

[Offmymeds]

I've been pH'ing the juice to 5.8 or slightly lower. The runoff has been registering 6.4. Not sure why I thought to test the res this AM but the juice I put in the res last night tested at 6.5. My res normally maintains a gallon when "empty" to keep the pump primed and I add 3 gallons to top it up. (In hindsight I should have made a slightly bigger res.)

Has anyone else had this experience? I have not idea why this would happen.

 

[jondamon]

I've been pH'ing the juice to 5.8 or slightly lower. The runoff has been registering 6.4. Not sure why I thought to test the res this AM but the juice I put in the res last night tested at 6.5. My res normally maintains a gallon when "empty" to keep the pump primed and I add 3 gallons to top it up. (In hindsight I should have made a slightly bigger res.)

Has anyone else had this experience? I have not idea why this would happen.

Recirculating? Drain to waste? Coco? Soil?

You’re not really giving much to go off.

If recirc

ph increase usually means ppm decrease so plants are feeding increase ppm.

 

[Offmymeds]

Recirculating? Drain to waste? Coco? Soil?

You’re not really giving much to go off.

If recirc

ph increase usually means ppm decrease so plants are feeding increase ppm.

Thank you. It's drain to waste in coco but this is happening in the reservoir. There is no plant interaction there.

 

[jondamon]

Thank you. It's drain to waste in coco but this is happening in the reservoir. There is no plant interaction there.

Are you filling with tap water and then adding nutes and then pH’ing?

If so the water from tap will settle and off gas a little bit which will alter pH.

always best to check after 24 hours too to make sure.

I do the same with mine.

Fill 25L top up can

Adjust nutrients

adjust pH

Add to reservoir.

Mix for 10 mins check pH.

Next day check pH again as it’s usually altered slightly in pH.

Granted .7 pH rise is quite a lot so I would also ask about your source water starting ppm/EC etc?

 

[jondamon]

Also RUNOFF pH is coco is never correct.

The only thing you may want to do is test nutrient strength in runoff from time to time.

trying to adjust input pH to match runoff pH will have you chasing your tail.

 

[Offmymeds]

Thanks again. I'm not too worried about it but it seems odd. I'm using RO. The mix of nutes was Jack's 3-2-1, silica, & fulvic acid. The res is being aerated and has a chiller holding the temp a hair below 70. I plan to make a little extra juice to hold outside the res next time to see if there is a difference.

 

[jondamon]

Thanks again. I'm not too worried about it but it seems odd. I'm using RO. The mix of nutes was Jack's 3-2-1, silica, & fulvic acid. The res is being aerated and has a chiller holding the temp a hair below 70. I plan to make a little extra juice to hold outside the res next time to see if there is a difference.

Are you adding any buffering salts or Calmag to stabilise the pH?

Also aerating water can cause pH jump.

I use just a small hydro pump to circulate my reservoir rather than trying to inject Oxygen into the water.

stops stagnation and keeps the nutrients mixed.

 

[jondamon]

Like this is all I do with mine.

1 pump to feed and one just mixing.

but I have it pointing up towards the water surface so it disturbs the surface and causes rippling

 

[Offmymeds]

Like this is all I do with mine.

1 pump to feed and one just mixing.

but I have it pointing up towards the water surface so it disturbs the surface and causes rippling

View attachment 5060652

Looks like a great idea but how do 2 pumps affect the water temp?

 

[myke]

Check your RO filters,maybe its time for a clean?

 

[Offmymeds]

Check your RO filters,maybe its time for a clean?

I just changed them prior to this. PPM so low it won't register. on my Blue Lab truncheon.

 

[myke]

Then its most likely the buffers in your food causing the jump.

 

[jondamon]

Looks like a great idea but how do 2 pumps affect the water temp?

I don’t even worry about water temps but the water feels cool to the hand as one pump is on 24/7 and the other runs for 1 minute every 3 hours.

 

[Offmymeds]

Then its most likely the buffers in your food causing the jump.

Good thought. I'm going to mix only Jack's with silica on the next feed, no Recharge, no larvicide, & no fulvic acid & let that sit overnight to see if there is a change.

 

[Treesomewanted77]

Looks like a great idea but how do 2 pumps affect the water temp?

What I do with my circulation pump is put it on a timer so it runs for 5-10 minutes every 2 hrs and doesn’t raise temps at all. Use the smallest pump you can and that will help keep temps down but in coco drain to waste the res temp shouldn’t matter much i wouldn’t think anyway. But not a 100% on that

 

[Offmymeds]

What I do with my circulation pump is put it on a timer so it runs for 5-10 minutes every 2 hrs and doesn’t raise temps at all. Use the smallest pump you can and that will help keep temps down but in coco drain to waste the res temp shouldn’t matter much i wouldn’t think anyway. But not a 100% on that

I believe the temps must be kept low to stop the microbes that cause root rot. If they form in the res they will get to the plants. I try to take no risks with root rot so I use a $125 aquarium chiller and an air pump. That's probably overkill but root rot is a devastating yield & time killer so I'd much rather be cautious & ultimately happier.

 

[Treesomewanted77]

I believe the temps must be kept low to stop the microbes that cause root rot. If they form in the res they will get to the plants. I try to take no risks with root rot so I use a $125 aquarium chiller and an air pump. That's probably overkill but root rot is a devastating yield & time killer so I'd much rather be cautious & ultimately happier.

You may be right but I think it coco you can have micros that won’t hurt the plants it actually helps them. I keep my coco water at 80+ degrees for weeks at a time and no treatment and I add recharge and photosynthesis plus often. I’m not a 100 % weather it’s beneficial or if it’s harmful because I only ran DTW in coco for a short time before going back to flood and drain

 

[Offmymeds]

I discovered through the process of elimination that my problem was the Jack's Part B I was using wasn't properly stored. It had become damp.

Problem solved.

Thanks to all for help.

 

[DesperateFarmer]

I discovered through the process of elimination that my problem was the Jack's Part B I was using wasn't properly stored. It had become damp.

Problem solved.

Thanks to all for help.

Wet calcium nitrate? What would make it slowly drag it up? I had the same issue in ebb flow with nutrients being used up, coco being not rinsed, and with a heavy dose of brown sugar and great white microbial making beer. Also with humic acid sometimes it takes longer to go into solution and can raise it over time as well.
Just some various insights of my own