Noob question about ph rising In standalone res

Hey guys, growing 8 Dwc buckets (no recirc) and tried mixing up a 20g batch of nutes for the buckets.

Temped out the water to 68, added all of the nutes, ended up at 6.1 ph. Added some down to get to 5.8, monitored it for 15m before heading to bed and it was stable.

Woke up today and checked the res bin which was closed and has a couple of airstones running and it ph had bumped back up 6.1, thought the temps had dropped.to 64 (cold basement)

This is only my second time mixing several days worth of go juice. Is this a ph buffer issue or possibly a minor swing from temp drop? Should I just readjust the ph.to.5.8 at current temp and hammer down?

When mixing a batch of nutes for my buckets,.I figured I should ph the water somewhere close to the 70ish degrees in the buckets. But I don't know shit haha.

Thx guys

Colder = higher ph when water isn't pure.

zen0n said:

Hey guys, growing 8 Dwc buckets (no recirc) and tried mixing up a 20g batch of nutes for the buckets.

Temped out the water to 68, added all of the nutes, ended up at 6.1 ph. Added some down to get to 5.8, monitored it for 15m before heading to bed and it was stable.

Woke up today and checked the res bin which was closed and has a couple of airstones running and it ph had bumped back up 6.1, thought the temps had dropped.to 64 (cold basement)

This is only my second time mixing several days worth of go juice. Is this a ph buffer issue or possibly a minor swing from temp drop? Should I just readjust the ph.to.5.8 at current temp and hammer down?

When mixing a batch of nutes for my buckets,.I figured I should ph the water somewhere close to the 70ish degrees in the buckets. But I don't know shit haha.

Thx guys

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Your pH meter should adjust its reading based on water temp. I use a Bluelab but I don't know how the different brands handle that. I've used inexpensive pens but took the plunge for the Bluelab Growers Toolkit. The pH pen and the EC pen are backlit and they're waterproof (hmm, wonder if they float?). Overall, I find them much easier to work with than the $20 devices.

Rising pH is a normal condition, though 5.8 to 6.1 overnight is pretty quick. I've attached the WonderChart and Son of WonderChart (my nicknames). Track the three values - water uptake, EC/PPM, and pH - and use those values to determine what's next.

I had a grow in 2017 where I "chased pH" and, I'm doing a second grow now, where I took a different approach. I walked the PPM from 520 to 750 in 10±% steps and didn't get a stable res so I walked it back down until I hit 490 (autoflowers apparently use far less nutes than photos) and there is now peace in the valley at 490 to 520. The res responds in a very predictable, consistent manner. Huge change from 2017.

That's not to say that your TDS should be 520 — I found the sweet spot by systematically changing TDS until the res was stable. In the case of these 4 Gorilla Glue autos (in a 35 gallon res), everything's jake at 500±. If you're growing photos, you TDS will probably be higher.

I am running larger rez for first time and it just takes a few days to balance it out. I run an under current system and my rez Temps are around 65 degrees. It takes three days of adjusting my ph down before it stabalizes qnd that's after filling my system with water already Ph'd to 5.8. By morning after the first day of changing rez I go from 5.8 to 6.5 like clockwork. I add 20ml of Ph down qnd 15 min later I am at 5.8. Next morning I am around 6.20 I add 20ml again. Next morning I am at 6.0 qnd that is usually where I leave it qnd slowly get it down to 5.8 through my top offs.

I run 500-550ppm in veg and around 750 in flower with my current photos.