Happened almost overnight! Phosphorus deficiency?

Good morning!

Stumbled upon this checking out my plants this morning

I use LED’s in a flood & drain set up, currently in early growth stage, full line of GH (I’m only giving 1/3rd the dose into 30 gals of neutral PH water w/ a blue lab up/down controller) and I just added ~6 gallons of water 2 days ago and some supplemental nutrients! Maintain a 70 degree room with ~50-60% humidity.

I’m assuming this is some sort of phosphorus deficiency, roots look good, only two plants have been affected - I’m sure this is a dumb question but what should I do?!

You haven’t mentioned whether your source water is Reverse Osmosis or tap or well water.


You haven’t mentioned what your EC or PPM’s are when you fill your reservoir and what they are after a days worth of running your flood and drain system.

You should be monitoring the pH and EC/ppm on your return water to be able to see how your plants are feeding.

Are you pH’ing your nutrient/water mix after you’ve added your nutrients or before?


You’re running a full hydro setup so you should be monitoring your nutrient and ph levels of your reservoir.


Based on how your plant looks in the picture I would say you could do one of two things.

1. Increase flood frequency

2. Increase nutrient strength and keep frequency the same.


But without knowing what I mentioned above it’s hard to say for sure.

Usually with younger plants when a deficiency appears it’s usually caused by either

pH incorrect
Low nutrient strength

Thank you very much for trying to address my problem - I apologize for the missing information.

I use well water, I live right next to a river, the water is pretty decent and has a neutral pH (the guy I bought the house from was a prosperous florist & grew all flowers here).

I think you narrowed it down for me, probably didn’t soak & get the pH corrected in the expanded clay balls, I’m going to flush the system & soak some more clay tonight and adjust from there.

I’ll post back any info when I get it with a update.

Thanks again!

On plants that small, it's usually not a problem that can be solved by adding nutes.