Phosphorus Deficiency Help Please

[Meakanu]

Howzit guys. I’m on my first grow and have been having some issues with one of my plants. Yesterday I finally was able to ID it as a phosphorus deficiency due to some of the lower leafs.
The plant is on day one of week6 flower today, it’s in a 10 gallon pot of super soil.
I watered it this morning with Plane water PH’ed to 6.5 and took a run off sample. The run off PH was 7.2 and had a PPM reading of 2,350, witch seems really high to me.
Anyway after doing some research it seem phosphorus lock out occurs when Soil has a lower PH. So I’m not sure the PH being a little high is the issue.
I’m thinking I should just give it a PK boost but wanted to get some more experienced input before taking action.

 

[CaliRooted]

I grow in super soil in 7 gallons, I just went through this same problem, I was thinking phos was locked out too. I believe the ppm reading, mine is off the charts as well, however I don't PH anything being Organic I feel is counter productive. Just my opinion. What are you putting in the soil mix to buffer pH? Dolomite? When mine are as green as yours at week 6, I just let mine roll.

 

[Meakanu]

I grow in super soil in 7 gallons, I just went through this same problem, I was thinking phos was locked out too. I believe the ppm reading, mine is off the charts as well, however I don't PH anything being Organic I feel is counter productive. Just my opinion. What are you putting in the soil mix to buffer pH? Dolomite? When mine are as green as yours at week 6, I just let mine roll.

I added a small amount of Dolomite when I mixed the soil. Other then that I just ph my water using PH Up/Down. I have 6 plants in my room, 3 in super soil and 3 in CoCo. The other two plants in soil arnt having any problems.
My SS mix was about half strength so I started feeding them a small amount of nuts about once a week after they went into flower. I’ve fed all three of the soil plants the same nuts and everything.
I checked the Run off ph and PPMs of the other two also and they were also 7.2 and 2,400ppm.
Only thing difrent is the plant having issues was my biggest going into flower and has about twice as many bud sights as the other two.

Attached a pic showing the three soil plants, the one in the middle is the one with the issue. All same strain from seed.

I’m thinking I’ll just give it a little PK boost and let it ride after that sense I’ll probably start flushing next week anyway.

 

[GT21]

Dont add more till you get the ph right... youre wasting nutes.... ph soil to 6.8

Do you have purple stems too?

 

[Meakanu]

Dont add more till you get the ph right... youre wasting nutes.... ph soil to 6.8

Do you have purple stems too?

Stems are green.
How should I lower the soil PH?
I know with the Coco I would just flush it with lower PH water until what’s coming out reads at what’s going in. Not sure is soil is the same process?

 

[CaliRooted]

How long did you veg in the 10 gal? Timing is everything with this SS. My last run was 50/50 the 50 with the phos issue were bigger than the other 50 that stayed green till the end. Yeah your stems look great. My leaf damage was identical, and purple stems showed up as it progresses.

 

[Meakanu]

How long did you veg in the 10 gal? Timing is everything with this SS. My last run was 50/50 the 50 with the phos issue were bigger than the other 50 that stayed green till the end.

Vegged for one month

 

[CaliRooted]

Hmm I only veg in my 7s for 10-12 days. I veg in 1 gallons for 2.5 weeks then 2 gallons for 2.5 weeks then 10-12 days in 7s then flip. My last run I vegged a week longer and had this problem. The run before was flawless. As far as pH I just never have.

 

[oldskol4evr]

i would leave it alone as far in as you are,said flushing next week right,,there is no super soil,you have to feed it all the way anyway,the life in soil is super soil,,like gt said wasting nutrients