Question on Cal-Mg and PH

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SeedyScene

SeedyScene

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Hello, I am a new grower and a new mbr to this forum. I am growing in coco. I have had three failed attempts with my first grow due to cal-mg deficiencies that I was unable to remedy each time. Clearly, I'm doing something wrong and I've done a lot of troubleshooting over these three attempts with no improvement. I'll list my latest grow details below, but here are my basic questions since there's a lot of mixed info out there on this:

- Most sources say that when growing in coco, in veg set the PH to btwn 5.8 - 6.0, which I have done with each grow attempt. However, when I look various PH Charts for coco/soilless, the Calcium doesn't seem available until at least the 6.0 mark. Setting the PH to 5.8 - 6.0 seems a bit on the low end. Should I continue to set PH in veg at 5.8 - 6.0?

- When flushing b/c of a nutrient issue, I have been using tap H20 (144ppm/300EC) and adding 25% nutrients to the water. I have NOT been setting PH. Should I set PH for flush water, and if so, what should it be? Should I be using 25% nutrients when flushing?

Thanks for any info you can provide.

Grow Details
Medium: Coco (70% coco / 30% perlite_
Plants: fem autos, Ethos Genetics
Nutes: CANNA Coco A & B, their Rhyzo, Cannazym and Boost
Other Additives: Cal-Mg supplement (5ml/gal with every fertigation); Recharge brand microbials; Southern AG fungicide
Light: HLG 350R LED, and using T5 for 1st two weeks before switching to LED
Watering: I have been following forum member Aquaman's method for watering coco with all 3 grow attempts.
 
Tracyfri

Tracyfri

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Hello, I am a new grower and a new mbr to this forum. I am growing in coco. I have had three failed attempts with my first grow due to cal-mg deficiencies that I was unable to remedy each time. Clearly, I'm doing something wrong and I've done a lot of troubleshooting over these three attempts with no improvement. I'll list my latest grow details below, but here are my basic questions since there's a lot of mixed info out there on this:

- Most sources say that when growing in coco, in veg set the PH to btwn 5.8 - 6.0, which I have done with each grow attempt. However, when I look various PH Charts for coco/soilless, the Calcium doesn't seem available until at least the 6.0 mark. Setting the PH to 5.8 - 6.0 seems a bit on the low end. Should I continue to set PH in veg at 5.8 - 6.0?

- When flushing b/c of a nutrient issue, I have been using tap H20 (144ppm/300EC) and adding 25% nutrients to the water. I have NOT been setting PH. Should I set PH for flush water, and if so, what should it be? Should I be using 25% nutrients when flushing?

Thanks for any info you can provide.

Grow Details
Medium: Coco (70% coco / 30% perlite_
Plants: fem autos, Ethos Genetics
Nutes: CANNA Coco A & B, their Rhyzo, Cannazym and Boost
Other Additives: Cal-Mg supplement (5ml/gal with every fertigation); Recharge brand microbials; Southern AG fungicide
Light: HLG 350R LED, and using T5 for 1st two weeks before switching to LED
Watering: I have been following forum member Aquaman's method for watering coco with all 3 grow attempts.
How far along did you get before throwing in the towel? How big/old were your plants when the issues began to occur?
 
SeedyScene

SeedyScene

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Around the 3 week mark, but the issues always start around Day 10, like clockwork.
 
Allegedly

Allegedly

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ok so, medium looks good, i dont recommend autos to new growers because you dont get to make mistakes and recover like you do with a Feminized photo period plant. That being said theres nothing wrong with an auto you just wont get to bounce back the same.

- a PH of 5.8 is the sweet spot in coco for VEG, it hits almost everything nutrient wise. but its ok to shift around every day or two a couple points like one day you feed 5.8, the next 5.9, 3rd day 5.7 and so on, or just stay at 5.8 and call it good. yes continue with around a 5.8 PH from germination on through veg.

- tap water is fine to feed and flush, your PPM/EC is in a good range from the tap if those numbers are correct although i would not be adding 25% nutrients and would rely on a PPM/EC feed chart and the look of your plants health to determine whether to bump up or hold back on nutes.

- Yes you are going to need to PH the flush water, and I would mix up your nutes to the strength you want and flush until the ppm of the runoff is in the range you need to be. *(coco drying will increase your PPM rapidly and trash your plants if unchecked too long. dont let your coco dry out much if you can help it. you can feed in coco 1, 2, 7 times a day without drowing the plant as long as air can get in, water and salt can get out and the plant isnt too cramped.

- careful with the light hight youll fry those babies if you have that down. that light says 18-24 inch mount height above canopy but thats probably for flowering, just watch it so theyre not frying the seedlings, the R spec lights are great I have the 550R but its more geared toward flower, it can handle veg but isnt as efficient as a something with more blue light in the spectrum. (that doesnt mean it sucks, you have a great light) ***just saw you use a T5 for seedlings, thats probably a good idea but be careful when switching to the 300R that you dont smoke the plants on day 1 of swap because that is a massive difference in heat and light.

-it looks like you might just be feeding too hard too early but I cant say for sure. seedlings need so little the first week or two, basically keep em moist and give em light, then no touchy.

***edit*** dropping in a chart that shows coco and soil ph ranges
***edit 2 cause i cant get it together lol*** i recommend checking out cocoforcannabis dot com. youll learn everything you need to know and help weed out conflicting information.
Nutrient Chart2
 
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Tracyfri

Tracyfri

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Oh, NS so they just barely got their first set of serrated leaves then and start to kibby out on you then. Shouldn't b an issue to get you up and running. You'll be going strong in no time.
Day 10 of Seedling.
 
SeedyScene

SeedyScene

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ok so, medium looks good, i dont recommend autos to new growers because you dont get to make mistakes and recover like you do with a Feminized photo period plant. That being said theres nothing wrong with an auto you just wont get to bounce back the same.

- a PH of 5.8 is the sweet spot in coco for VEG, it hits almost everything nutrient wise. but its ok to shift around every day or two a couple points like one day you feed 5.8, the next 5.9, 3rd day 5.7 and so on, or just stay at 5.8 and call it good. yes continue with around a 5.8 PH from germination on through veg.

- tap water is fine to feed and flush, your PPM/EC is in a good range from the tap if those numbers are correct although i would not be adding 25% nutrients and would rely on a PPM/EC feed chart and the look of your plants health to determine whether to bump up or hold back on nutes.

- Yes you are going to need to PH the flush water, and I would mix up your nutes to the strength you want and flush until the ppm of the runoff is in the range you need to be. *(coco drying will increase your PPM rapidly and trash your plants if unchecked too long. dont let your coco dry out much if you can help it. you can feed in coco 1, 2, 7 times a day without drowing the plant as long as air can get in, water and salt can get out and the plant isnt too cramped.

- careful with the light hight youll fry those babies if you have that down. that light says 18-24 inch mount height above canopy but thats probably for flowering, just watch it so theyre not frying the seedlings, the R spec lights are great I have the 550R but its more geared toward flower, it can handle veg but isnt as efficient as a something with more blue light in the spectrum. (that doesnt mean it sucks, you have a great light) ***just saw you use a T5 for seedlings, thats probably a good idea but be careful when switching to the 300R that you dont smoke the plants on day 1 of swap because that is a massive difference in heat and light.

-it looks like you might just be feeding too hard too early but I cant say for sure. seedlings need so little the first week or two, basically keep em moist and give em light, then no touchy.

***edit*** dropping in a chart that shows coco and soil ph ranges
***edit 2 cause i cant get it together lol*** i recommend checking out cocoforcannabis dot com. youll learn everything you need to know and help weed out conflicting information.
View attachment 1158571

Thanks very much for the clarity on this. I think you might be right about feeding too aggressively too early. Regarding light distance, I am using mfgr's recommendations but I will back off a little more on light intensity when I do the switch from T5 to LED. I also have been using cocoforcannabis.com as my other main resource. I've been toying with growing photoperiod instead of autos for my first grow since, as you say, the autos are not as forgiving. I think I will do that.

I greatly appreciate the information you have provided me and will apply it to my grow.
 
SeedyScene

SeedyScene

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pictures please?
You'll see in these pics my 3 plants at Day 18. At day 12 I started to see some red/purpling on some leaf stems and slight leaf edge twisting. By Day 15, many leaves started to develop wrinkles and ends pointing down. As of today (no pics), rust spots have taken over some leaves.
 
0816211000
0817212138 HDR
0817212138a
Allegedly

Allegedly

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more close ups of rust spots and light green/yellow spotting
I'm not sure its magnesium, I do see problems you've had with it in the lower but the lower looks good compared to the top. do you have a fan blowing down on them or your light turned way up? only curious because its affecting the top primarily. and most of the bottom leaves look smooth and happy by comparison.
-In the mean time i would check runoff PPM and PH next time you feed and see where you are with that.
 
SeedyScene

SeedyScene

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I'm not sure its magnesium, I do see problems you've had with it in the lower but the lower looks good compared to the top. do you have a fan blowing down on them or your light turned way up? only curious because its affecting the top primarily. and most of the bottom leaves look smooth and happy by comparison.
-In the mean time i would check runoff PPM and PH next time you feed and see where you are with that.
Thanks. I did have 2 6" fans moving them around, directed mostly at the top of the canopy. I have lessened the air flow strength and am giving them more indirect air now, with one fan instead of two. It does look like there could be wind burn. and, my LED is at 45%, which may be too strong for a 3 week old plant, so I've backed off on it.
 
Allegedly

Allegedly

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Thanks. I did have 2 6" fans moving them around, directed mostly at the top of the canopy. I have lessened the air flow strength and am giving them more indirect air now, with one fan instead of two. It does look like there could be wind burn. and, my LED is at 45%, which may be too strong for a 3 week old plant, so I've backed off on it.
whats your hang height from the top of the canopy? the 2, 6 inch fans probably aren't too much as long as they aren't hanging like a foot away and beating the plants around. I have the 6 inch hurricane fan and it doesn't very much air.
 
SeedyScene

SeedyScene

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whats your hang height from the top of the canopy? the 2, 6 inch fans probably aren't too much as long as they aren't hanging like a foot away and beating the plants around. I have the 6 inch hurricane fan and it doesn't very much air.
yes, I am using 2 6" hurricane fans and they were about 14" away. My HLG 350R is 24" from top of the canopy, as recommended by mfgr, but I think my light intensity was maybe too high. HLG says 60-80% for veg and I had it at 45% at week 3 veg.
 
Allegedly

Allegedly

178
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yes, I am using 2 6" hurricane fans and they were about 14" away. My HLG 350R is 24" from top of the canopy, as recommended by mfgr, but I think my light intensity was maybe too high. HLG says 60-80% for veg and I had it at 45% at week 3 veg.
i mentioned that about the height earlier. thats likely your flowering height, that leight is built for flowering and they (used to i dont know now) sell the blue model for veg. like i was saying earlier you can do it with the R, I do with my 550R. but i cant turn up anywhere near the supplier specified numbers or i fry everything. i would raise the light a foot and leave the power the same, see what the plant does for a few days and go from there. go with your gut on the fans. if it isnt moving your plants all over the place its ok, you need the air circulation.
 
SeedyScene

SeedyScene

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i mentioned that about the height earlier. thats likely your flowering height, that leight is built for flowering and they (used to i dont know now) sell the blue model for veg. like i was saying earlier you can do it with the R, I do with my 550R. but i cant turn up anywhere near the supplier specified numbers or i fry everything. i would raise the light a foot and leave the power the same, see what the plant does for a few days and go from there. go with your gut on the fans. if it isnt moving your plants all over the place its ok, you need the air circulation.
They told me flowering height is 15" from canopy. Still, I think I'm giving too much light too early in veg so I'll back off. I do use T5 fluorescents for the first 2 weeks. Should I use them for longer before making the switch to LED?
 
Allegedly

Allegedly

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I have to apologize, I made a minor mistake. I had it in my head you had the 300L r spec. I didn't even know the 350r had been released, and it does look like it has a nice blue spectrum in there. I do see now where you're right, it does say 15" flowering height. I was trying to look through their insta to get any help or advice and found a couple little clues but nothing crazy.

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Allegedly

Allegedly

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i do find it odd that they want you to move a larger light, with 90 more potential watts, closer to the plant than the other. but I am certainly no expert on any of this. just a guy with a couple years experience trying to help troubleshoot :) I just might make a mistake.
**edit** the 350R is a commercial lamp and they are probably factoring in C02 implemented in the grow (if im not mistaken lets you drive the plants harder with feed and light intensity but again i can make a mistake i dont use C02). with that being said they may be giving recommendations based on that and you could reach out to HLG and ask but ive had pretty crappy luck with responses from them, takes a while sometimes and its vague.
 
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