How can I stabilize my ph (major fluctuations)

I'm having pretty severe issues with ph. This is my second DWC grow but is my first with RDWC. My ph will rise from 5.5 to 7.2 in as little as 8 hours . My last grow never had problems with ph it was always 5.3-5.7 with very minimal need for ph adjustments . This time I've used the same tap water , same flora trio nutrients with cal-mag. The only difference is this time I'm running 2 resivours instead of one. I also have the 2 resivours hooked together via 2 1" lines and have a chiller cooling them .. no I do NOT have a control res (ran out of room)
PS. I have a new BlueLab ph meter I thought my cheap one was giving me wacky reading but it is giving the same reading as the blue lab

1.My question is will recirculation make ph harder to control than standard dwc
2. Will distilled water make my ph more stable

Pic is before I added the cooler and hooked the resivours together
Any advice is welcome

Did you rinse your hydroton with non-ph'ed tap water?

I did for several minutes but there still not smooth like the last grow

Take them back out and rinse them real well. Or use new hydroton and rinse it.
PH some water to 5.8 or so and soak the hydroton for 24 hours.
You should be good. Your PH should be staying relatively stable at the point you are at.

Distilled water will make your PH more unstable because it does not have the carbonate buffers tap has btw

Are you adding your ph adjusters straight, or diluting them into a solo cup of water first, let it diffuse.. Then slowly add it and stir.

If you add it straight, the res climbs the next few days for me .

I've always added them straight . Never thought about mixing it first

5BY5LEC said:

Take them back out and rinse them real well. Or use new hydroton and rinse it.
PH some water to 5.8 or so and soak the hydroton for 24 hours.
You should be good. Your PH should be staying relatively stable at the point you are at.

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I've still got half of a bag so I'll start fresh .. I'll rinse them and let we soak for 24 hr

NCSmallTime said:

have a chiller cooling them

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are you running nutes thru the chiller? does it have copper, stainless or titanium innards?

Yes I run nutrients through the chiller . I dont know what type of metal the coils are . It is a active aqua hydrofarm 1/10hp . I looked online and couldn't find anything about material

NCSmallTime said:

Yes I run nutrients through the chiller . I dont know what type of metal the coils are . It is a active aqua hydrofarm 1/10hp . I looked online and couldn't find anything about material

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it should be stainless i think. copper and nutrients don't play well together.

you sure you don't have any root rot going on? that will raise pH too.

No roots are bright white there still seedlings around 10 days maybe 12 days old . Only a few roots have. Made it to water level

I'm going to drain it and give everything a good bath whe I get home and start with new water and nutrients and see if it will help any . What's the best cleaner to use for the res

NCSmallTime said:

I'm going to drain it and give everything a good bath whe I get home and start with new water and nutrients and see if it will help any . What's the best cleaner to use for the res

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Dawn anti bacteria dish soap. Non scented.
A dish cloth or metal scrub pad for dishes.

If you want to get real clean, wipe with bleach afterwards. Let sit for half hour and rinse very well

I like 91% iso because it evaporates quickly and does not leave a residue.
Once you have everything soaked and ready, your first fill set your PH a bit low, maybe 5.6 because its gonna rise a few points overnight maybe .3 or so. I use tap, Trio, Silica and Calimagic so I imagine you are going to see that same rise I do. This should only happen the first night after you do a res change. The second night it should be stable or rise .1 at the most.
Like RKY said you need to also keep a good eye on those roots. Anything but white and you better start running bennies or sterile.
Whats your tap PPM btw?

I think its 130s

That's not bad. I run about 70-90 depends.

I just thought of something when I made my first resivour I used hydroponic purpose glue when I made the second I used marine glue to hold the air stones and pumps in place I'm wondering if that has something to do with ph

air stones can also raise pH.

me personally would get 2 very small waterpumps, some tubing and elbows and make a waterfall in each tote.

rkymtnman said:

air stones can also raise pH.

me personally would get 2 very small waterpumps, some tubing and elbows and make a waterfall in each tote.

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Same here. Also if you do plan on using airstones, you haveto remove them once n a while and clean them.

Go with a waterfall . Air pumps blow dirty air into your res. Its not that efficient either .