Uc4 Nutrient Advice

[jasonn33]

Hey just hoping someone can give me some advice, I've done a lot of reading and here's my current grow with some issues and pics.
UC4 28 gallon res
-1 x 1000 watt light highest daytime temp 86f lowest night time temp 72f
-lucas formula from veg to 3rd week flower
-chiller 1/10hp water temp 68
-Compost tea brewed weekly
-master kush strain
-nutradip trimeter ppm reading 930, seperate ppm meter reading 950
-ph set to 5.8 dropped to 5.6 over 2 weeks
- GH lucas formula 8/16 since rooted - 3rd week flower
- flowered at 17 inch and now its at 43 inches

OK so overall the plant growth seems great but from my research looks like I have nitrogen toxicity or close to it. I find it weird because lucas formula suppose to be low nitrogen and I notice some of the younger leaves at the nodes of the buds canoeing nothing major but dark green leaves and canoe suppose to be nitrogen abundance right? What I noticed over 3 weeks of flower is that the ppm slowly rose and ph very slow dropped so I diluted from 940ppm to 850ppm which would mean I'm kinda deviating away from the lucas formula and I thought it was suppose to be pretty solid for most strains. The tips had minor nute burn also I began to dilute as soon as I saw that. Currently I drained all the water except for whatever that was left that the pump cannot drain and filled with tap water that has ppm of 20 max and just letting it sit for 24-48 hours, total ppm 120.

Really new to dwc in general and hope someone can shed some light, I understand that dwc and undercurrent in general uses much lower ppms but I have read people running lucas in undercurrents before. Heres a couple question if anyone has an idea or some suggestion feel free, is lucas formula simple GH 8/16 micro bloom or is it a 1/2 ratio maybe I can continue to use the ratio but at lower ppms? plant was vegg for 4 weeks since rooted and never had a problem with lucas formula till now. While researching a question that came to mind was maybe the bennies from the compost tea is either producing nitrogen or making it more available so the plant is taking in a lot more, again that is just a theory and I'm a noob. For people wondering why I run bennies, I tried uc roots/h202 temp at 64-66f and roots were never as good as with bennies. Any help is appreciated thanks!

 

[DapperDon]

Okay, I have to ask. When was the last time you calibrated your Tri-meter? Also are you using RO water? Because I read that your tap water was @20 ppm and that is insane. Most RO systems fight to get there so I am thinking your equipment is off. Dump the teas. Those are great for dirt farmers, but a UC has to run clean. Use bleach instead of overpriced bottled nonsense. But you are correct that they are showing the signs of N-Tox and lockout.

 

[FooDoo]

I don't use bennies and stopped using chlorine. But for you, if it ain't broken, don't fix it. I see nothing wrong with running teas if you like the results .

Lucas is pig rich in nitrogen. 130 ppms worth of it. I find nitrogen toxicity in uc around 100 ppms. Ive ran 85 ppm and it was perfect.

Your overall 900 ppm is too high..that is why your pH drops. But its not a dramatic over night drop so that's not too bad. I think maybe the bennies are helping cushion that. Your pH range is decent, thankfully you're not like everyone else who's running 6.1, getting def, and acting surprised.

I'm also not seeing too much nitrogen toxicity in your leaves. I just tested a new mix of 104 ppm nitrogen on my triangle kush moms in dwc buckets and I got the limp tips almost over night. Your girls are looking decent. Dark. But decent.

What makes you so worried?

 

[jasonn33]

Thanks for the replies, the tri meter was calibrated right before flower and I actually have hand held ppm and ph pens all reading around the same range. My tap water really is that good and probably the only thing I'm sure of anymore lol.

I'm worried about some minor canoeing on young leaves, all signs would point to N toxicity if its completely possible to N overdose on lucas then I think I'm nearing it but I'm new at this. Here are some pics of the leaves that are rustling my jimmies.

 

[FooDoo]

Yea. Just cut your micro back some.

 

[jasonn33]

Ok thanks, after the flush I have now set the ph to 5.8 ppm to 780. I will update in a week!

 

[Genesis]

What kinda Master Kush you running, seeds or clones? I ran Sensi Seeds Master Kush and got a great yield, smoke pretty nice but nothing crazy In The effects or taste department.

 

[jasonn33]

Hey genesis I got them as clones from a friend, he said he can't get them packing on weight but the smell and taste are great, lol kinda opposite of you guess.

 

[Genesis]

Hey genesis I got them as clones from a friend, he said he can't get them packing on weight but the smell and taste are great, lol kinda opposite of you guess.

Well that sounds nice as well :), hope you are happy with the cuts man. There are many 'Master Kush's' out there.

 

[jasonn33]

Heres an update, I started at micro bloom 1:2 ratio 780 and ppm increased the next day so I diluted to 700 and ppm was still rising so I lowered to 550 ppm was holding steady at around 550 micro bloom 1:2 but I notice nute burn and the plants seem to kinda stall on eating water level was dropping little too slow so I flushed for 48 hours ph 5.8 plain tap water 40 ppm.

After 48 hours re-nuted at micro bloom 1:2 but extremely low levels of 360 ppm. At this point ppm was dropping by 10 per day, ph fluctuated, and water level dropped a lot faster. It seems whenever I add fresh nutes ph dropped, I ph at 5.8 and it would drop to 5.6 in 2 days I then ph 6.0 and it dropped to 5.7 but eventually went to 5.9 super weird. I read somewhere to just stop chasing ph problem as long as its in acceptable range so ill leave it at that.

Finally it looks like I have calcium deficiency which is not surprising at such low ppms so here's the question should I stick to micro/bloom 1:2 but just raise the ppm? Or add calmag? Any help appreciated!

This isnt my plant but it look identical to this.