I am no DWC expert Rp but I believe that is a sign of the plants eating the nutrients. My understanding is, nutrients lower the ph of your liquid. As the plants take up the nutrients and leave the water behind it begins raising back to the normal ph of your water which is closer to 7.0. I have only one grow hydro grow but that is what I noticed every time mine would raise in ph I would check the ppm and it would be lower than I started with.
Spot on info bro :smokebuds:don't think it applies in this case though ,RP's babys are to small to be having those affects on a res that size in that short a time .
If I thought they where drinking even a small percentage of that res id consider this theory but looking how small they are there's no way there minute feeding habits at this stage will be causing the mad PH swings.
Its worth remembering for later in the grow once the res is being emptied & what you mention is a perfect indicator of underfeeding A4 ...ie- the nute strength is not perfect (a bit to low) so the plant consumes the nutes faster than drinking the water ....diluting the nutes & making the EC drop ,resulting in the PH rising .
Same vice versa ...ie -If the nutes are to strong the plant drinks the water faster than eating the nutes & they get more concentrated ,making the EC rise ,resulting in PH dropping.
The idea is to get the EC perfect so the plant drinks & feeds at the same rate ...when EC & PH remain stable the plant is taking them up at the same rate & your in the zone :dance:Thing is all this happens a bit later in the grow & right now (especially with EC so high) I would guess something else is the cause ?.
Not sure what your using for media there RP ?. but that may be effecting the PH ..it does not look very light proof or something ive seen used before.Plus the orange top parts of your buckets look semi transparent ?
Id say your PPM's so high for such small plants is the issue with possible light getting in somewhere ? .... shoot for around 400 ppm & cover up that cotton wool media or whatever it is with something light proof to be sure :smokebuds:
