ppm rises as ph drops........

[theguapo]

...as my reservoir PH drops by adding nitric acid (I use technaflora PH down) the ppm rises. This makes sense as more is being added to the reservoir but someone answer this please. Lets say my reservoir PH is 7.5 and ppm w/nutes is @ 450. I want to lower my PH to ~5.5 and when doing so the ppm raises to 700. Do I consider the 700 as too much for the plants at that age, targeting 450, and compensate by reducing nutrient levels or ignore the raise in ppm, knowing that prior to lowering the PH the targeted ppm was reached? I'm sure this question has been answered before but I didn't find it anywhere.

 

[motherlode]

never used technaflora ph down, but it shouldnt be adding ppms to your mix, at least not that damn much

 

[nononsense]

...as my reservoir PH drops by adding nitric acid (I use technaflora PH down) the ppm rises. This makes sense as more is being added to the reservoir but someone answer this please. Lets say my reservoir PH is 7.5 and ppm w/nutes is @ 450. I want to lower my PH to ~5.5 and when doing so the ppm raises to 700. Do I consider the 700 as too much for the plants at that age, targeting 450, and compensate by reducing nutrient levels or ignore the raise in ppm, knowing that prior to lowering the PH the targeted ppm was reached? I'm sure this question has been answered before but I didn't find it anywhere.

how old are yer plant?

 

[theguapo]

that's what I thought but it seems to be really affecting the ppm. i'm gonna dump the res manana and start with fresh distilled H2O and see what happens.

 

[Smokey503ski]

I use the PH up and down. My question for you is are you diluting your PH stuff before you add it to your rez? Sometimes if you ad your PH stuff to fast it can cause Nutrient Fallout. That is where the PH messis up the food you have in your res. Also are you having alot of temperature fluctuations in day and night with your rez?
If you can please explain the step you take in filling your rez will help figure out the issue.

 

[theguapo]

I've been adding the PH down directly to the res and waiting about 30 minutes before measuring the PH. there is only about 2 degrees fluctuation in res temp throughout a 24 hr. period. i'm gonna dump the res and start fresh today so i'll dillute the nitric acid before adding it and see how that affects everything.

 

[motherlode]

you should never add ph down directly to a res, you should buffer it by adding the amount of ph down your going to use to a gallon of water first and then slowly add that to the res...

 

[UCMENOW]

Add RO water to your res.....this will bring pH down and dilute the nutes for better plant uptake.

 

[theguapo]

I think i've got a handle on it. I appreciate the replies, really. Before res changes I prepare RO water a few days in advance so on res. day change i'm ready to go.

 

[tortuga1503]

R/O solves many issues

 

[doBpop]

Perhaps this will help:
How do I tell if my PPM/EC is too high or too low?

​

 

[Jalisco Kid]

Add RO water to your res.....this will bring pH down and dilute the nutes for better plant uptake.

How does adding RO lower your pH? JK

 

[Larry Benwa]

How does adding RO lower your pH? JK

If your ph is above nuetral and your RO is 7.