pH up and down

[Friedumpling]

Hey everyone!

So I’m on my first hydro grow and I thought I remember reading or seeing something that advised against using pH up and down in the same reservoir.

Usually I fill my res at about 5.9-6 and if it drops off, I tend to just top off water with my tap water that comes in higher. I’ve got a good system worked out where I am 9/10 able to balance it back out to the 5.9-6 range.

This past week, it was dropping off and by today it dropped off too much with no room to just add higher pH water. Thankfully I was only a day away from res change day, so I just swapped out today.

So after all that, my question is this:

Can you use both pH up and down in the same reservoir without creating issues?

[gbauto]

Welcome, Friedumpling,
Yes, it's ok to add both to the same rez. They are designed to neutralize each other. When I ran GH Flora trio, it would always start @ 5.5 and I would slowly raise the pH to 6.5 over the course of 10-14 days. This allows all of the micronutrients in solution to be fully available to the plant.

[Cali]

From what I have read here onGWE you are not supposed to mix or use both up and then down on the same resevoir. Nebula has a video showing you how to ph the water and she says clearly if you over do it with either one you have to start over with fresh batch of water because you are not supposed to use them together..

[FlyingDutchPaddy]

Hi Friedumpling , seems that some manufacturers recommend not to use them together...

https://www.google.com/search?&q=using+ph+up+and+down+together

The page from hydroponics.co.uk suggests not to use them together:
"NEVER use pH Up and pH Down together. If you’ve accidentally used too much pH Down, DO NOT use pH Up to correct the problem and vice versa. If this happens, we recommend you dispose of the solution and make a fresh batch as mixing pH Down and pH Up can have a chemical reaction and render the nutrient solution unusable."

In my experience, my tapwater is around 7.0 so I add pH down to get it to around 6.4.
Over the course of a few days I notice that pH levels drop... (2 days after water change pH is 6.2 ; started with 6.4)
Mixing with plain tap water gets it back to desired levels.
Rarely do I need to add pH up to bring pH back into desired range.

I'm using GH Flora trio for nutes, and most likely GH pH buffers are designed to work well with those nutes so as not to interfere with the solution.

What I'd do: check to see the manufacturer of your nutrients to see if they also make pH down/up that work together with their products.

Another tip I got from here was: add H2O2 (Hydrogen Peroxide) to the water every once in a while.
That has helped me keeping pH levels from dropping from 6.5 at water change to 5.5 a week later.

GH also recommends that if you use extra CalMag, add that first to the water before adding the Micro.

Hope that helps.

[Friedumpling]

Thanks for all the info. I knew I wasn’t crazy when I thought I had seen the info somewhere.