Plant dies 1/2 way thru blooming stage.

[Grower1]

So I’m fairly new to hydroponic growing. Been doing it about 2 years. I had a very successful first few grows. Than I found spider mites on my plants. After 2 more grows (trying to get rid of the spider mites...to no avail) I Noticed my plants dying about halfway thru the blooming stage. I chalked it up to the spider mites. So I stopped all growing all together, waited a few months and started up again.
Im on my 3rd plant now and have no problem with vegetative growth but this is my third plant that is about to die at the halfway point of blooming.

Can an some one help me?

[s62]

If you can give us as much data as possible about your grow (like temps, ppms, light, distance, etc.) it will help a lot. Also, please add pictures. They’re truly worth 1000 words.

[Grower1]

I’m not a high tech grower. I have a PH pen. When I read this plants PH it was around 4.5. I know too low. I added PH up to it (is it normal to see white crystals drop to the bottom of the tote when you add PH up) and now the PH is 6.1. The plant doesn’t seem to be doing better but hasn’t died yet. The light is HIgh sodium and is about 3’ from the plant. Temp of room and water is all average temps. 70s to 80s. I don’t know about ppm’s Or how to read them or adjust them. I’m using general Hydroponics 3 pack nutrients and in doses on the bottle. I took a picture and I’ll try to attach.

[az2000]

If you've determined with a loupe/scope there are no bugs on the undersides of the leaves, then there must be something wrong with the nutrients (the strength, or NPK ratio). Or, your air temps/humidity are way off. Or, the res temp is off (slime on the roots, root rot).

When was the last time you calibrated your ph and ppm pens? (I saw someone have enormous problems due to this.).

You say you "chalked up" the last failed plants to mites. You didn't actually see mites? Did you examine the leaves with a scope?

[Grower1]

I did look for bugs. Saw none. Roots at real healthy and white. Air and water temps are all normal. I’d say 70 - 80 degrees. PH pen is new and I checked the calibration out of the box. I did see note with a scope on old plants. Also saw their webs all over the plants.

[Grower1]

[az2000]

What do the roots look like? What's the res temperature? I've never grown hydro. But, they look overwatered. Not sure what that means in hydro. But, I bet it has something to do with roots having slime, water temp to high, not airated enough, etc.

[Guest]

I don't know anything about hydroponics. I just wanted to stop by and say this breaks my heart to see it happen to somebody. you're really putting a lot of time and energy into those plants I could tell. They have big stalks. They almost look like they're hungry.

None the less I hope the pictures help somebody diagnose what you got going on there. I know the roots are importantand you say they're nice and white and doesn't smell funny.

Hang in there