Clawing new growth, light color, and a deficiency

I'm running Lucas as well, and am having great results. I'm doing the 8/16 in a rdwc system that holds 28g water. PPMs are 890 and ph 5.7. They don't seem to mind all the nutes, and are growing like crazy. Are you using a sterile rez or beneficial bacteria to control pythium outbreaks? How do those roots look? Still pearly white? It almost looks like a ph problem to me, maybe ph lockout? I had a ph lockout issue once due to a crappy ph pen, and the ph was close to like 5.2-5.3 even though the pen read 5.8, so I got some of the ph liquid test also just to double check, and some calibration solution. If the bulb on the pen dries up, it can malfunction. One thing to note, my ro water prior to nutes is close to 8.0, after adding everything it does down to 5.3 and I add a little ph up to get to 5.7. Tripple check that ph!

I'm no expert, but looking at the ph chart for canna, the reason i'm thinking ph issue, or lockout is because the tops are pretty yellow (lack of N) and purple stems can be lack of (P), and perhaps some Mg too. Maybe get closer to 5.8 ph, or at least flush with higher ph water maybe.


Girls in Lucas 8/16 rdwc. Running GH Micro & Bloom w/ Calmag (ro water) and dutch master zone (roots are going crazy)
They have been in this system from clone for 2 weeks as of now.

rkymtnman said:

just to be clear: you have 2 grows going on right? some are in flower (12/12) and others are just starting right in veg?

and snafuu is correct. save your CO2 until you get everything else perfect. unless your in a closed room with a ppm monitor for the CO2, it's just a waste.

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Yes everything in flower has been great ! Co2 is in there !

seems like you are close then. i think you'll be fine once you cut down the nute strength a bit and work them up to higher ppms.

what ppm CO2 are you running?

rkymtnman said:

seems like you are close then. i think you'll be fine once you cut down the nute strength a bit and work them up to higher ppms.

what ppm CO2 are you running?

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Well I'm saving up for a titan controller so for now I just follow this chart. My room is about 280c.f. i had to buy the titan temp fan control cause up here in the mountains my intake fan brings in too much cold air, I even bring it thru the light first so I bought the controller for that.

sounds good. keep us posted on how things turn out

Change veg res and it is at 300 ppm. I guess since I'm going to start changing every week I don't need to fil it to 20 maybe go down to 10 and top it for a week then dump it !

those ppms should be much better for the young ones. if you still see the clawing, try even an even lower ppm and slowly work your way up.

the best advice i ever got for hydro is to give a 24hr flush and start back on weak nutes.

Just wish I would see some new growth or improvement !!!

rkymtnman said:

those ppms should be much better for the young ones. if you still see the clawing, try even an even lower ppm and slowly work your way up.

the best advice i ever got for hydro is to give a 24hr flush and start back on weak nutes.

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I'm not getting any signs of improvement, growths has came to a halt :/. Never had this happen where everything went south. I've been checking for bugs cause I know broad mites can cause this but I'm not seeing anything and I have a good skope. Just so weird that a flush did not show better signs.

Usually when the stems turm red it's because res temps went above 69F and algae starts to grow. An excess of mag crops up and lockout.

bird mcbride said:

Usually when the stems turm red it's because res temps went above 69F and algae starts to grow. An excess of mag crops up and lockout.

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Well I only use lucas formula and have not added anything. I'm in combo I doubt they got over 75 ish, could too cold cause this ? I know it can stunt Croats but lows is around 65 ish.

When there was new growth appearing it was just going straight into a claw.mi can figure it out.

steezy wonder said:

Well I only use lucas formula and have not added anything. I'm in combo I doubt they got over 75 ish, could too cold cause this ? I know it can stunt Croats but lows is around 65 ish.

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what is your light schedule for the young plants?

are your flowering ones going from 75F to 65F?

24 on. I have Been flowing those. My flower room gets up to 82 ish I can go way higher or lower pretty easily

good. 24/0 is perfect for veg.

have you seen any new growth?

maybe go a little lower in flower room. how about 78F? and lights off you want areound 65 to 68F.

In denver now I'll look when I get home. At the drain side of the table a little water sits so I'm going to raise the cubes by adding more hydroton . I don't think that's causing this cause one end drains and they are the worst ones.

Just change the res every 4-7 days and keep the water temps somewhere between 65-69F. the damage will not repair itself but the plant(s) will out grow the damage.

bird mcbride said:

Just change the res every 4-7 days and keep the water temps somewhere between 65-69F. the damage will not repair itself but the plant(s) will out grow the damage.

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Temps are at 66 res just got changed

So these are the photos I took tonight. I have added more hydroton too raise my cubes up more out of the very little bit of left over drainage water. Photos where taking during water on. I'm water 3 times in 24 hrs, cut back from 4.


What most of the tops look like, some black on the edges but not too dry


About 3-4 of the top bigger fan leaves are getting brown on outside


New growth on this is not too bad


These bottom ones are a little crutch and folding up


The 2 newest clones are looking ok.

Here is where I'm at today.


Some new growth



Still have this rust at the top of 2 plants. Cal mag I think. I added 3my per gal. The lowest rec. Should I foiler anything ? I have Epsom too. Small clones are still ok as well as flower. A little dark leaves so I dropped ppm to back off N.