What could cause this?

[Pyru]

Lower leaves looking horrible

Ph 6
Tap ec is 0.06


Res ec was 1.6 then upped to 1.8

water change dropped res water temp from 70 to 59 (maybe shocked?)

now after a water change i have ec at 0.95 and res temp 65

i also recently added h2O2 and a few drops of hb101 before recent water change (maybe this did it?)

 

[Waira]

...she looks nute' roasted bro',...the severe clawing, dead leaves,.... the yellowing on newest growth could be either Fe or S deficiency starting, or even Mg at this stage,... I'm not a DWC expert, so I'll scare up somebody who is,...hang tight!... :Sharing One:

 

[DWCocha]

Id say Waira is spot on again bro .1.6 up to 1.8 is way to strong for a auto seedling .Bringing it back down under 1.0 is the right thing to do & you may start to see new growth soon ,but you have to have PH in the right range & 6.0 is to high for seedlings also ...needs to be under 5.8 at this stage .

So you may have some nute lock out from feed & PH being way to high.

I remember my 1st few attempts at DWC went very similar to what im seeing here & it was mainly due to having cheap meters giving false readings & putting way to much nutes in at the start .Less is more with hydro bro ,its better & less stressful to be underfeeding them & they really dont need much for the 1st few weeks ...week 1 I usually just run water until the 1st root hits the res ....week 2 a weak feed of just baby feed (formulex) & some root stimulator (rhizotonic) ...they dont even get the veg nutes until about 3 weeks in ,then once they take off & are well established you can up the feed weekly & keep it at the right level by monitoring PH & EC.

If you give us a run down of what you have for nutes & what you added to the last res in what order I may be able to advise on the next one ?.:Sharing One:

 

[Pyru]

All I've been using is general hydro flora nova grow nutes, although before this started I did add a few drops of hb101 and some h2o2