Phosphorus deficiency or what?

Good evening everyone I need your help to figure out this deficiency. The reason I’m having issues figuring it out is, it does not match any of the information online.

So it is mainly affecting the higher up leaves. When I trim them off it pops up next day all over others. It is mobile obviously since it’s bouncing around. It also doesn’t affect the edges but mainly the center of the leaves.

I think it’s phosphorus since it’s in flower and it seems to be the closest looking pictures but again nothing matches it exactly.

I may have over fed last week so I skipped a feeding and just watered the next time. The PPMs were 1600 and then 2 days went by and it was 900ish I gave just water. It’s been an issue for like two weeks.
PH water 6.7-6.8 every 2 days or so going by weight.

Wasn’t sure if it could be light burn but I’ve turned the light down and DLI is lower than normal ( I think I have it at 35 right now) and light is 12inches away ( high as I can get it).
She is a big girl, she’s bulging out the side of my tent 2x4x4 ( 4 wide 2 deep and 4 tall)
If it is I have AN Bud Blood I was going to use to give a highly concentrated shot to her but wanted to confirm.

Happy frog soil 3 gallon pot
Sour Diesel autoflower
Feeding Lotus Nutes ( boost and bloom full strength)
PH is great, last water was 6.5 in and 6.3 out.
Temps are 72-80
RH 50%
Have used recharge and bud candy for feeding Mycho

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1.5 gallon of water every 2.5 days or so based on weight ( she is definitely ready when I water her)

Next time you water try to get runoff ppm and ph numbers. From there you can ger a better idea what’s going on. Here are some charts to refer to. It does look like a phosphorus issue but before adding anything make sure your ph and ppm range are where you’d like them and then look on your nutes and up the one with phosphorus a bit. Just my 2 cents. Feel free to wait for more experienced users to comment


Are you using beneficial microbes? Hydroguard is what I use with Hydroponics.
Could be a fungus causing rust spot.

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I am, using Recharge and Orca.

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I forgot to add I did flush 6 days ago and got PPms good and PH good.

It definitely seems to be spreading fast. I’ll check PPMs either today or tomorrow when it needs watering.


It does appear to be a phosphorus deficiency and could have some calcium deficiency as well as these 2 nutrients interact together in the plant. Are you feeding base nutrients along with the flower boost and bloom? :love_you_gesture:

I’m doing the Bloom and Boost which supposedly has everything it needs. Even has the macro nutrients which is why I wanted to do Lotus nutrients. I have been giving 5ml per gallon of CalMag recently according to the bottle I have ( the CalMag plug forget brand it’s liquid). I fed it the last few times. Also last feeding yesterday I gave a little more of the bloom than normal since it has more phosphorus and I gave some Epsom salt instead of the CalMag.

@GrowingIs4Everyone hey i know this is an old thread but i came across it…did u come to a resolution to the cause of the problem?

I did not unfortunately. It ended up getting worse but it survived and the harvest was amazing it just want a pretty Instagram worthy plant :rofl:.

Reason is i got the same thing goin on with my sour d was it calcium?

She 41 days above soil sour d auto she got the rust spots im thinking calcium or phosphorus but i supplement with both