Plain Water pH keeps rising. Please Help.

myke

Well-Known Member
IIRC some of the salt water fish dudes would add a little ph up first,this gives ph down something to grab on to and hang around longer?
 

PadawanWarrior

Well-Known Member
I use 26 ppm water for my DWC system. No nutes, no additives, nothing. pH is around 7.2.

I lower the pH to 5.8-6.0 using Terra Aquatica pH down, and after like 3-4 hours, pH goes back to 7.0.

I again add pH down and reach 5.8 pH, wait another 4-5 hours and it is still the same. I repeated at least 5-6 times.

I changed the container several times, now I use a food grade container, and the result is still the same.

Same happens if I add nutes as well. I lost many seedlings due to pH fluctuations for the last 4 months. I tried everything, it feels like a spell/curse.

Please help. I started laughing hysterically by myself at home.
Sounds like it's your water. Probably hard water that has calcium that wants to raise it back up.
 

ChrispyCritter

Well-Known Member
I use 26 ppm water for my DWC system. No nutes, no additives, nothing. pH is around 7.2.

I lower the pH to 5.8-6.0 using Terra Aquatica pH down, and after like 3-4 hours, pH goes back to 7.0.

I again add pH down and reach 5.8 pH, wait another 4-5 hours and it is still the same. I repeated at least 5-6 times.

I changed the container several times, now I use a food grade container, and the result is still the same.

Same happens if I add nutes as well. I lost many seedlings due to pH fluctuations for the last 4 months. I tried everything, it feels like a spell/curse.

Please help. I started laughing hysterically by myself at home.
You need to add something to "pure" RO water, a buffer, otherwise the ph will never stay anywhere except 7 if you don't mess with it. There is nothing to ph.
 

waterproof808

Well-Known Member
You need to add something to "pure" RO water, a buffer, otherwise the ph will never stay anywhere except 7 if you don't mess with it. There is nothing to ph.
yeah, usually cal-mag is added first as a buffer, then base nutes, then adjust ph. At least thats how it was done when I used veg+bloom.
 

1212ham

Well-Known Member
How are you measuring ppm ? 26 ppm is pretty soft water , hard to imagine it has enough carbonate hardness to keep raising ph above 7.0 . Any chance your tap water is going through a water softener before coming from the faucet ?
That's what I was thinking... 26 ppm shouldn't push the ph up. There has to be more to this story.
 

kubat

Member
How are you measuring ppm ? 26 ppm is pretty soft water , hard to imagine it has enough carbonate hardness to keep raising ph above 7.0 . Any chance your tap water is going through a water softener before coming from the faucet ?
I buy bottled water, it is almost RO so that I can have more room for nutes, I set PPM around 250-300 for 10-12 days old seedlings.

I just measured ph 10 mins ago, it is again around 8.5. Test kit is as purple as it can be. Here is how I had prepared a gallon of rez:

I added Terra Aquatica Silicate just enough to raise the PPM from 26 to 70, and made it sit 10 hours.

Then mixed it well, and added AN Micro, Grow, Bloom; in that order, mixing well each time. Then 0.5 ml Biobizz Hydro compatible Cal-Mag, very tiny amount. Then fixed pH to 6.0 (Urine color yellow with Terra Aquatica Test Kit) PPM was around 270

After like 8-10 hours, pH was 8.5. I really laughed hysterically all by myself in the middle of the night.

Now I removed the airstones, after fixing the pH, the hoses give big bubbles now. I will measure after another 8-10 hours. If it rises back again, I will go for 5 gallon big buckets.
 
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Hollatchaboy

Well-Known Member
I use 26 ppm water for my DWC system. No nutes, no additives, nothing. pH is around 7.2.

I lower the pH to 5.8-6.0 using Terra Aquatica pH down, and after like 3-4 hours, pH goes back to 7.0.

I again add pH down and reach 5.8 pH, wait another 4-5 hours and it is still the same. I repeated at least 5-6 times.

I changed the container several times, now I use a food grade container, and the result is still the same.

Same happens if I add nutes as well. I lost many seedlings due to pH fluctuations for the last 4 months. I tried everything, it feels like a spell/curse.

Please help. I started laughing hysterically by myself at home.
Nothing in the water really to buffer the pH?
 

kubat

Member
organic cal/mg? i'd find something else salt based.

and try a waterfall to aerate and skip the airstones.

probably leave out the silica too for now. just the 3 part. and something for root rot.
I use silica just to stabilize ph. What do you suggest for root rot? We dont have Hydroguard here in this country
 
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