Clawing new growth, light color, and a deficiency

Over the past few days my veg tent has slowed down growth and started getting a rams horn. I just switched my res yesterday and I'm flushing for a few days now. I'm using an ebb and flow system with a t5. Trying out the lucas formula now and it's been working great till this point, I even have 4 in flower with this method as it has been working. I have one leaf up top that has some browning and wondering if it's cal mag issue. Strain is purple elephant about 4 weeks in.


Thanks for any help.

The only leaf with the browning is that one at the very top.

Its called clawing ...and is a sign of over nuting the next stage is the leaf tips dry out and spread to the leaf stem going a horrid yellow, then death to that leaf

cut back your nutes by 50% for the next 10-14 days, monitor close,

note the red stems ...keep an eye on your night time temps

good luck

I'm using lucas formula which is 5/10 per gal. My res is 20gal so I'm going to nuts it to 10 gal. Night time temps to warm ? Highest they get is 75 low is 71 consistently ! I live in colorado and their in a loft. Just got to looking and my stems on my 2 flower ones got very red / purple over the past 2 days what do you think about that ? Just sprayed neem oil so pardon that. The plants look great other than the stem show, is that an early sign of anything or are they good ? I think it's just my cold temps, the flower room gets down to 66 ish

I flushed for 3 feedings, now nutes are in at 50%. Now how long till the claw goes away or new growth comes in ?

are you using RO or distilled water with lucas formula?

you can go lower than 5/10 ratio too. i'd back it down to 3/6 and see how they react. if looking good, go up to 4/8 and then 5/10

rkymtnman said:

are you using RO or distilled water with lucas formula?

you can go lower than 5/10 ratio too. i'd back it down to 3/6 and see how they react. if looking good, go up to 4/8 and then 5/10

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I'm using tap water here in the mountains of co, comes out at 140ppm so I've never had an issue with it. I did 5/10 at 10gal instead of 20gal after changing my res. I'll keep it there for a few days. Just crazy all the new growth is like that. They were great the whole time. I did top off and add more per the formula but never had an issue till this week. I guess there was more nutes from topping it off A few times. The top leaf that shows that browning is the very top one and deficiencies usually start from the bottom up correct ?

what is your total ppms? how about your pH? in the range of 5.5 to 6.1? your pH should be going up and your ppms should be going down.

most deficiencies start at the bottom.

i use lucas. i only topped off with plain water. then change res every week.

I waited 2 weeks as I've never had a problem till this week. Ppm at 590, ph 5.9. You say ppm goes down, as you top off and add your nutes back do you not try to maintain your ppm or do you just top off with tap until there is more tap then nutes and flush it then ? Any extra tips on lucas would be nice, there is so much and so far it's been great. At what points do you add cal mag and any other micro nutes ?

A few more photos. The one of the 2 small clones has been in there 3 days, so far so good on them. The small one a week and has not done much. They both came from aero cloner and had tons of roots.
These are 3 days in and look good

All growth has seem to claw and then stop.

Been in 6 days and no new growth

steezy wonder said:

I waited 2 weeks as I've never had a problem till this week. Ppm at 590, ph 5.9. You say ppm goes down, as you top off and add your nutes back do you not try to maintain your ppm or do you just top off with tap until there is more tap then nutes and flush it then ? Any extra tips on lucas would be nice, there is so much and so far it's been great. At what points do you add cal mag and any other micro nutes ?

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i think i see the issue. your ppm is way too strong for those small plants. that's why you have the clawing. too much N. i hardly go over 1.0EC (roughly 500ppm) even in full flowering. at those size, my EC is around 0.2 (100ppm).

i've done lucas for over 6 yrs now so i'm fairly experienced with it. here's what i'd do: flush with pH'd water for 24 hrs. always my first step if having issues. next, mix up a batch of nutes using 2mL micro/ 4 mL bloom for however many gallons you have. feed that to them for a few days. they should start to look better. if so, mix up your next batch at 3/6. then go to 4/8 and up to 5/10 if still looking good.

i never liked the add back part of lucas. here's why. let's say you mix up a batch at 5/10. what if the plant uses lots of N but not much P or K? then when you addback, you replace the missing N but now your P and K are way too much. i mix up batch on day 1. top off with just plain water for the rest of the week. dump on day 7 and mix up a new batch. repeat. repeat. repeat.

you "shouldn't" need cal/mg with lucas. micro nutes are in the micro bottle so extras not needed.

lucas is great. the only thing you might want to try is using RO water. i'm in CO too on a well with about the same ppm as you. i still fill up 5 gal jugs at walmart with RO. it just makes everything easier. i use about 10 gals a week.

all that make sense? if not, ask away. more than happy to help!

its your tap water.

looks like a lot of people have this problem. they switched my water source due to the droughts in CA and my water before was around 200ppm was fine. my new water is 900 ppms and my plants did the same thing. check the ppms of your water

That's awesome info man than you. I flushed for 3 feeding then put in half strength and it's been 24 hrs. Would it be a bad idea to just change about 1/2 my res and check the ppm again ? I was thinking for veg <600 ppm flower 900+. Am I way off here ?

MrStickyScissors said:

looks like a lot of people have this problem. they switched my water source due to the droughts in CA and my water before was around 200ppm was fine. my new water is 900 ppms and my plants did the same thing. check the ppms of your water

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140 is what my tap is. Have not had the issue in the past.

steezy wonder said:

That's awesome info man than you. I flushed for 3 feeding then put in half strength and it's been 24 hrs. Would it be a bad idea to just change about 1/2 my res and check the ppm again ? I was thinking for veg <600 ppm flower 900+. Am I way off here ?

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nowhere near that high of ppms. especially now when they are small and only under t5's. if you want to try something, take a gallon jug, mix up a batch at 2/4 and see what your ppms are. go with that for at least 3 days and see how they do.

i know lucas says you can feed right from the beginning with 5/10 or 8/16 but it always nute burned the shit out of my plants.

with small seedlings, i start at 1/2 and SLOWLY work up to 5/10.

i use EC so find a conversion chart. i go with around 0.1 to 0.2 to start. at full on flowering, i "might" get as high as 1.2 your 900 ppm idea is almost 1.8EC which is way too strong.

i think a 24hr flush is good enough. if you flush for too long, you run the risk of running into deficiencies.

Headed to hydro store for more co2 then I'll test a gallon and try to get my red around that.

You dont need co2 until you're dialed in.

You're a long way off.

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.