Grow Mediums RDWC pH issues - I haz clay pebbles

[Boradan]

Having an issue with Rez changes and pH.

My system is running a few decimal places around 6.0 generally.
When doing a rez change, I check the current rez pH and then set the new fill at the same pH (generally 6.0 to 6.2)

When I actually drain the current rez and replace it with the new, correctly pH'ed rez, the pH after an hour or 3 goes through the ROOF.
I am talking 6.9-7.2 pH.
I am sort of convinced that it is due to the crap from the clay pebbles - even though I washed them for about 20 minutes and then pHed some water and kept them in there for 24 hours before using, I notice there is a LOT of crap sediment still in the bottom of my pots/rez from the pebbles which then gets back into circulation when I hit it with the new water.

Any opinions/pointers???

 

[Free Flow]

Thats too high for hydro.

I set my ph to 5.6 when changing and by the time I change my res I find that they only swayed up to 6.2. Even after checking them,the following day my ph only drifts from 6.1 to 5.9 the life span of my 4 gal res until the last 2 inches or so then it goes to about 6.2.

 

[Masterkush87]

Having an issue with Rez changes and pH.

My system is running a few decimal places around 6.0 generally.
When doing a rez change, I check the current rez pH and then set the new fill at the same pH (generally 6.0 to 6.2)

When I actually drain the current rez and replace it with the new, correctly pH'ed rez, the pH after an hour or 3 goes through the ROOF.
I am talking 6.9-7.2 pH.
I am sort of convinced that it is due to the crap from the clay pebbles - even though I washed them for about 20 minutes and then pHed some water and kept them in there for 24 hours before using, I notice there is a LOT of crap sediment still in the bottom of my pots/rez from the pebbles which then gets back into circulation when I hit it with the new water.

Any opinions/pointers???

I am also having this issue, i havent done a rez change but so far every time i set my ph, it goes to around 7 the next day, i have soaked the pebbles also but just with regular tap water:/ its frustrating as i think this is really affecting the plants

 

[Boradan]

I am also having this issue, i havent done a rez change but so far every time i set my ph, it goes to around 7 the next day, i have soaked the pebbles also but just with regular tap water:/ its frustrating as i think this is really affecting the plants

Fortunately, mine only takes 20 to 30 minutes to raise (it takes 15 minutes for the rez to circulate through the entire system), so I measure the pH after about 45 minutes and then add pH down, so it shouldn't affect the plants that much. I was just wondering WHY it happens when I am pHing the new water/nutes before I change the rez

The plants seem fine :

 

[puggle6]

What's your base water pH reading?

 

[Chris Stroupe]

Having an issue with Rez changes and pH.

My system is running a few decimal places around 6.0 generally.
When doing a rez change, I check the current rez pH and then set the new fill at the same pH (generally 6.0 to 6.2)

When I actually drain the current rez and replace it with the new, correctly pH'ed rez, the pH after an hour or 3 goes through the ROOF.
I am talking 6.9-7.2 pH.
I am sort of convinced that it is due to the crap from the clay pebbles - even though I washed them for about 20 minutes and then pHed some water and kept them in there for 24 hours before using, I notice there is a LOT of crap sediment still in the bottom of my pots/rez from the pebbles which then gets back into circulation when I hit it with the new water.

Any opinions/pointers???

What is your responsibility tempatures? If the water temp is high this could possibly throw PH out of range..

Also what do your roots look like? Root disease could be another contributing factor .

 

[Boradan]

What is your responsibility tempatures? If the water temp is high this could possibly throw PH out of range..

Also what do your roots look like? Root disease could be another contributing factor .

Roots are perfect apart from staining caused by the Nute line I am using.
Air temps are 26C/21C (Day/night)
Water temps 18C +/- 1C

 

[MedGrower]

I've been having some raising pH problems also with Remo Nutrients at some random stages, but usually at the mid to late bloom parts. I've currently thinking if that would be an issue of too much bacteria growth in the reservoir due to feeding carbohydrates for benefical bacteria but I am not sure yet. Nature's Candy should have some carbs in it but I have not had that issue with it alone, but if I introduced Carboload to the mix, it seemed to cause this issue. Just speculation, I would need to try similar grows without it and then again with it so see if this can be repeated.

pH going above 6.3 with Remo line is going to cause some problems with P and Zn uptake so it is important to not let it stay high. I had that issue a lot with my latest AU grow.

What all are you having in your reservoir in what consetrations, how strong feed etc.? That would be useful to know so we can entertain some possibilities.

 

[EvilScotsman]

wee tip for cleaning out mediums mate.
dont rinse them. leave them in a big bucket of water and use your ph metre to tell you when its clean. change the water every day and when the water stays the same ph over night theyre good to go. had the same issue with rockwool, it took me a while to figure out and stunted a few plants in the process lol