Jacks RO nitrogen deficiency

Tolerance Break

Tolerance Break

Well-Known Member
I am running 5 plants under an HLG 100 on a 24 hour schedule, with jacks RO at 1.7 in the res, and a ph of 5.7. The medium is 4inch rockwool cubes. I had my EC too high last week, flushed with ph'd RO sunday, and since then, the growth has been stunted, and the plants have started to yellow. It looks like nitrogen deficiency, but that doesn't make sense to me. Could my nutes have gone bad sitting in a bag for 12 months?

I did this exact same set up last year and had much larger plants without these deficiencies popping up.

Here is a photo from April 24th, ill update the post when I get off work with today's photos.

Worst case scenario, I have 25 lbs of part A and B, so I might switch to those come res change. 20220423_150347.jpg
 
twentyeight.threefive

twentyeight.threefive

Well-Known Member
Tolerance Break said:
I am running 5 plants under an HLG 100 on a 24 hour schedule, with jacks RO at 1.7 in the res, and a ph of 5.7. The medium is 4inch rockwool cubes. I had my EC too high last week, flushed with ph'd RO sunday, and since then, the growth has been stunted, and the plants have started to yellow. It looks like nitrogen deficiency, but that doesn't make sense to me. Could my nutes have gone bad sitting in a bag for 12 months?

I did this exact same set up last year and had much larger plants without these deficiencies popping up.

Here is a photo from April 24th, ill update the post when I get off work with today's photos.

Worst case scenario, I have 25 lbs of part A and B, so I might switch to those come res change. View attachment 5125044
Click to expand...
Looks like your EC is still too high for those size plants, but I'm not familiar with Jack's RO, just 3-2-1. I'd raise pH to 6 also.
 
Cabrone

Cabrone

Well-Known Member
Sorry to see you having issues. I have been using 321 for a while, with Ro water. I was considering making the switch as you have. I run flood and drain buckets in hydroton and will definitely follow this, hoping you get some good advice.
 
Cabrone

Cabrone

Well-Known Member
Does the recommendation of 3 grams per gallon come out to 1.7 ec or are you dropping it?
 
Tolerance Break

Tolerance Break

Well-Known Member
So, I decided to lower the EC to .7 and raise the PH to 6, aaaaaand I accidentally left my pump on overnight, which had some interesting effects. There was noticeable root growth over night, one of the plants was praying, and the res PH jumped from 5.9 to 6.4.

So, I decided to flush all my rockwool cubes with ph 5.8 RO water (w/ a bit of hydrogen peroxide), dropped my res ph to 5.89, and let it run a little while to get some nutes back in the cubes. Now I'm waiting for them to dry out substantially before going back to the regular flooding regime.

Will update in a few days.
 
rkymtnman

rkymtnman

Well-Known Member
Tolerance Break said:
So, I decided to lower the EC to .7 and raise the PH to 6, aaaaaand I accidentally left my pump on overnight, which had some interesting effects. There was noticeable root growth over night, one of the plants was praying, and the res PH jumped from 5.9 to 6.4.

So, I decided to flush all my rockwool cubes with ph 5.8 RO water (w/ a bit of hydrogen peroxide), dropped my res ph to 5.89, and let it run a little while to get some nutes back in the cubes. Now I'm waiting for them to dry out substantially before going back to the regular flooding regime.

Will update in a few days.
Click to expand...
so you recirc with the rockwool blocks? how many cycles do they get before you redo the res?
 
Tolerance Break

Tolerance Break

Well-Known Member
rkymtnman said:
so you recirc with the rockwool blocks? how many cycles do they get before you redo the res?
Click to expand...
Once a week, 9 days max if I get too busy. I usually flood once a day, but I believe I am at the point where once every 12 hours is enough. I am toying with upping the flood time from 2 minutes to 5 or even 10 minutes, but Im not totally sure yet. My last grow I watered the cubes by hand until flower, and the roots just fucking exploded in flower. This time, I am getting waaaaaay better root structure flooding in veg, but I need to dial it in.
 
Last edited:
calvin.m16

calvin.m16

Well-Known Member
rkymtnman said:
i ran my RO always less than 1EC.

weird that i only see tip burn on some but not all.

i would maybe give an epsom foliar to the ones w/o tip burn and see how they look the next day.

12-4-16 "should" be plenty of N IMO.
Click to expand...
I need to bump this cause this post saved my ass. Jacks kept recommending 1.6-1.7 EC and I was wondering why my plants looked like shit. I lowered EC to 1.00 and without pH balancing (always lands 5.8-6.0 with pure RO mix) I have had zero issues, kinda fucky leaves but nothing too concerning.

I run Jack's RO 12-4-16 and just add and mix until 1.0 EC hits.
 
You must log in or register to reply here.
Top