major ph drop.. tips please

Can someone help me understand why I set it at 5.8/800 week 3 flower
then a day or two its at 5.25/748

When I looked at that black and white chart it's a little confusing. I'm assuming they need more food? When I dial in the proper PPM will it stay around the same PH?

What’s your water temp, nutes and additives? Just dwc? Air stones could cause issues with ph, bacteria as well.

Over feeding or root rot are 99.9% of ph crashes

water temp 65 deg, nutes are GH Flora Series, Calimag for calmag supplement.

Yes that's the chart I use. If I'm going by what it says I should Raise EC.

I'm also using an RO filter that introduces a small amount of cal mag into the base. It's only ever 15-30ppm after it filters. standard tap water was 260-300ppm at times so i had to filter it

J232 said:

What’s your water temp, nutes and additives? Just dwc? Air stones could cause issues with ph, bacteria as well.
View attachment 4794538

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I’ve had bacteria in a res whipsaw the pH down, then back up when they ran out of nutrient and lysed.

Aviatorshades said:

water temp 65 deg, nutes are GH Flora Series, Calimag for calmag supplement.

Yes that's the chart I use. If I'm going by what it says I should Raise EC.

I'm also using an RO filter that introduces a small amount of cal mag into the base. It's only ever 15-30ppm after it filters. standard tap water was 260-300ppm at times so i had to filter it

Click to expand...

How big is your system, when was the res change?

J232 said:

How big is your system, when was the res change?

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14 gal res, i changed res when flipped to flower 3 week ago. Roots are healthy and white

Aviatorshades said:

14 gal res, i changed res when flipped to flower 3 week ago. Roots are healthy and white

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I would be doing a res change, that seems more like a crash then a drop. If you look at that chart, a water level drop or static with drops would indicate a res change. I have only been into hydro since last year but I never experienced crashes when I used GH. How long have you been adjusting like this?

The water level has been dropping. Thanks for your help but I might wait for others to chime in.

It might say Res Change but it also says raise the EC. So rather than waste nutes and water, a higher EC could take care of the issue.

No prob, I would res change and up ec until I had the water drop with static ec. I would assume the ph will stabilize if your root zone is healthy.

Try upping the ec a little and see if anything changes.

I ran Lucas with micro bloom, it was very stable, if I pushed it too far, I ran into problems, 3-4 weeks I would have to intervene, attempted to run a no res change but partials worked too, I run between 80 and 90 gallons. I’m running dyna grow now, looking for a even simpler run.

Yeah but can't I just fix the PPM and not have to waste all the 14 gallons of water? How are you running 90 gallon systems after starting hydro only a year now? Every one talks about Lucas System do you have any decent links on it? From what I've read people say different things on each thread