Newb needs help

I currently have a northern lights big bud cross growing in a waterfarm unit under a thousand watt metal halide bulb (bat wing reflector. its a little over two weeks old. for the medium i am using three parts hydroton and one part vermiculite. nutrients are canna mixed with distilled water with the pumps coming on fifteen minutes every other hour. over the past few days it has gotten nutrient burn (which was my fault for giving it half strenght nutrients at less than two weeks old) I flushed with straight water for a day and a half but the burn still seems to be going steadily from the older leaves to the newer leaves. I currently have it at less than a quarter strenght nutrients hoping it will recover. now the stupid part. I realized that i had not put enough growing medium into the bucket and that it was only setting two thirds of the way up. probably should of left it alone but instead i replanted it up higher in the pot. the roots are mainly in the hydroton with most of the hydroton/vermiculite mixture on the bottom of the bucket at the tips of the roots. its been two and a half days since that and the older leaves are still wilted. the nutrient burn starts with the tips and edges of the older leaves as brown and then a crispy yellow then stops a few millimeters down the leaf and then the burn moves onto the leaves that have grown in the last week. overall it still seems to be growing and sprouting new leaves etc. can anyone offer some guidance or suggestions???

Are you using CalMag+? With distilled water, you need this supplement. Even though it looks like burn, the burn itself could result from a lack of nutrients also, causing the other unregulated/unbalanced mobile nutrients to burn up your plants.

where do i find it how much of it do i use etc? last nite i got magnesium and mixed it with water and a couple of the tips that were brown are starting to be recovered by green. any idea what thats all about???

A hydro store will have it. Not sure about Wal-Mart or Home Depot, they might have it also. If you're using a hydroponic system you should really have an EC meter...

http://boards.cannabis.com/hydroponi...lmag-plus.html

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Originally Posted by stinkyattic

If you don't have an EC meter, just use what's on the label, but you really should have some way of checking conductivity if you are in a position to need calmag, and you'll want to add it until your ppm reads right around 300, before adding any other nutes or checking the pH.

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As to your question of giving it magnesium, this is the best explanation I could find (it's for coco growing, but I think the same would hold true for hydro):

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Consequently, plants that do not have enough of some ions like calcium (there are several) due to underfeeding or washing out will show a deficiency in these and other elements. Meanwhile, potassium builds up the plant tissue, ultimately leading to margin burning on the leaf surface, mostly at the tip. The first thing the inexperienced grower assumes is that he is overfeeding and has salt issues. He will decrease the feed concentration and leach the medium. This, of course, magnifies the problem and makes it worse. The key to proper coco growing is to use the right feed to balance the products the coco gives off. Think not only about availability, but about the ratio of one mineral to another as well. It is also important to water correctly.

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Also, fill out the troubleshooting form at the top of this forum and copy and paste it here. There's a specific form for hydro. The CalMag may not be your only problem...

Novice

what type of hydro set up are you running? (waterfarm top drip

Your Equipment:
A) Type and wattage of lights. (MH and HPS )
B) Distance from tops?
C) Reflector type? ( bat wing)
D)1000 watt. dont know the rating. and currently 18 hours a day for vegging
E) Is there a consistent fresh air supply? YES
F) Do you have an exhaust fan and a circulation fan? YES three fans
G) Size of reservoir? 2 Gallon
H) What medium if applicable. Hydroton and vermiculite

Your nutrients and water:
I) If using rockwoll for clones or seedlings, did you rinse the cubes well, with properly ph'd water?
J) Source of water. (tap or filtered) What's it's ph? Tap water. 5.8
K) Specific brand and N-P-K ratio for each bottle. List dosages (quantity per gallon) and current feeding schedule. Canna aqua vega A and B also Rhizotonic. using two milliliters of each (1/4 the suggested dosage)
L) What is the ec/ppm of your unadjusted tap (or filtered) water? dont know
M) What is the ec/ppm of your nutrient solution? dont know
N) What is the temperature of your nutrient solution? (reservoir high and low temps) room temp is 82 high and 66 low im assuming close to that.
O) Does your ec/ppm show a rise or fall when you do your daily PPM check?
P) Does the ph fluctuate? YES
Q) Do you foliar feed? If so, with what, how often, and at what time do you
spray? (Just after lights come on, just before they go out...) YES Rhizotonic. no specific time.
R) How often do you replace reservoir water/nutes? What does it look like before changes? (clear, foamy, green, brown...) Every seven days. Clear.

Your growroom:
S) What size of closet, room or hut? 10x13
T) What are the temps and humidity levels while lights are on? ...With lights off? Lights ON temp 82 to 75. lights off 75 to 66. humidity 41 to 22
U) Have you seen signs of insects in the growroom? No
V) Are the roots long and white, or brown and slimy? long and white

Your strain:
W) What strain are you growing? (Indica dominate or Sativa dom?) big bud x northern lights. not quite sure
X) From seeds or clones? Seeds
Y) Is this an autoflower strain? NO
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