Spots on older fan leaves

[Doober]

Growing in dwc getting spots on older fan leaves. Plant is on 5th node right now. The first nodes fan leaves had same thing and eventually they died. Now starting on second node. I don’t have a clue. Rh is 40-45%. Ph is 5.8-5.9, I have a pump for the ph it lowers to 5.8 once it hits 6. I have a chiller that keeps water at 68. I always use Gh flora nova and have never had an issue. This strain is cap junky and does not like if ppm is above 540-550. I had it at 620 and all the leaves just drooped until I lowered ppm’s. I want to main line but not if there is trouble. Any help I’d really appreciate. Tia

[dec0der]

Looks like calcium deficiency. Do you feed it cal-mag?

[Doober]

Yes 2 ml per gallon

[Bluey]

I'd let the pH drift much higher before dropping it.

My aeroponics clones have never shown any leaf issues with once every 24 hour reset to 5.8 and I've seen them regularly hit above 6.5 at correction time.

After months in the aeroponics bucket, getting close to 2 foot tall and thebottom of the bucket with heaps of roots sitting in the solution ive seen the pH drop at times. Not sure though if it was that or maybe the airstone air tube got knocked out by accident. Can't remember.

[Pyrokill]

I've seen that on mine as a bad pH indicator. I was low so that may match your scenario. I do it in soil though. I grow my dope in soil I mean....

[Doober]

Ph has been ok.