Possible N toxicity; flushing questions

[Z Pops]

Problem: Pretty sure I have a nitrogen toxicity issue. Leaves showing slight clawing, each plant has had yellow/brown spots on one or two of the larger lower fan leaves.

Medium/grow method: Fox Farms Ocean Forest/Perlite (4:1)

Feed: and supplements used: Fox Farms trio, Cal Mag. 1/2 strength of feeding chart, watering every 3 days alternating between nutes and just pHed water.

water source: dechlorinated tap; pH to 6.0-6.8

Strain/age: Mephisto Orange Diesel week 8 from seed

light used: Mars Hydro SP-250

Climate: Day temp 75-77, night temp 65-66. Humidity 45-60%

Additional info: Runoff at ppm700 scale was way high after measuring from watering without nutes this morning (over 3000). pH runoff is around 6.0

Questions:

1. Pretty sure I need to flush immediately. 3x pot size would be 15 gallons per pot. I have 3x 5-gallon buckets but if I leave the water overnight to dechlorinate I can only flush one per day, correct? Or should I flush with straight tap water without leaving it to dechlorinate overnight and just hit each plant with 15 gallons immediately?

2. I just took these runoff measurements on my normal pH watering. Should I wait for the soil to dry out again before flushing or flush right away?

3. I think I caught this early enough. Agree/disagree? How much might this impact my yield?

Thanks!

 

[Builder0101]

The PH pen is it a 500 or 700 scale?

 

[Z Pops]

The PH pen is it a 500 or 700 scale?

700 scale

 

[Builder0101]

I see now you stated 700 scale. Sorry I missed that. Did you flush at 6.5-6.8?

 

[Z Pops]

i actually did not pH my flush water. pH from the tap is around 7.1

how big of a mistake was that? so far i flushed 2 out of 3 plants

 

[Builder0101]

No mistake. When in soil a flush should be done all at once. Don't want root rot/overwatering. Better to flush all at one sitting until you get the PPM down.
Probably best to flush at 6.5-6.8 keep things neutral. Yout temps should be 80° lights on. I keep mine at 82°-83° with a little Co2.

 

[Z Pops]

only reason i didn't flush all 3 at once is i only have 3 buckets. I wanted to dechlorinate so i left the 3 buckets out overnight and flushed one plant per day. day 3/plant 3 are tomorrow.

 

[Builder0101]

One watering without dechlorination will not hurt them especially if it means getting that # below 3k

 

[MesaBoogie]

One watering without dechlorination will not hurt them especially if it means getting that # below 3k

It's highly debated but testing shows that chlorine only kills bacteria suspended in water. The soils biofilm will neutralize the chlorine with it's buffering capacity.

Testing was done with batches of living soil that had been watered with chlorinated water and without. The lab results showed little difference in microbial life between the test batches.

 

[Builder0101]

I'd flush with 2, 3, 4 gallons of straight tap. Then 1 gallo. Each dechlorinated. Either way. At 3000 what is worse a tiny trace of chlorine which will not hurt them at all or waiting for days at 3000ppm