HELP! Nutrient Deficiency? Beginner growing in COCO

[MisterJones]

My new growth is looking like i have a nutrient deficiency. I dropped my PPM down to 400 for my most recent feeding because it looked like i may have had a Nitrogen toxicity. Growing in COCO. Growing with Mars hydro 600, ~78 degrees F, 50% RH. Can anyone help?

 

[growsince79]

What brand of coco is that? Was the perlite already mixed in?

 

[MisterJones]

What brand of coco is that? Was the perlite already mixed in?

It is Mother Earth pre-mix with 30% perlite. I did a cal-mag soak before i used it.

 

[growsince79]

It is Mother Earth pre-mix with 30% perlite. I did a cal-mag soak before i used it.

Ifs it loaded with nutes?

 

[MisterJones]

Ifs it loaded with nutes?

Nope. I believe it shouldn't really have any at all.

 

[growsince79]

Nope. I believe it shouldn't really have any at all.

I dont really see any sign of N toxicity. One burnt tip, no dark green, no claw. 400ppm isn't much. PH maybe? idk.

 

[MisterJones]

I dont really see any sign of N toxicity. One burnt tip, no dark green, no claw. 400ppm isn't much. PH maybe? idk.

I was just worried because the bigger fan leaves were somewhat shiny and darker green so i dropped to 400 ppm. Going to feed at 600 this time and see what happens. My fan leaves were more flat in the beginning but now they look like they're sort of cupping downward. The new growth looks like there are light green spots whch makes me think i need to up my ratio of Cal-Mag.

 

[Terpz719]

I get learning coco can be a bit tricky at first. What are you feeding them, pH, how often, how much run off? Are you supplying calMg with each feeding? If anything you might need to give them a bit more Mg. Don't see any N toxicity.

I've used Mother Earth coco for a couple of runs now, and haven't pre buffered, but the plants do get calMg with every feeding. Here are a couple of good resources:

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[Anthem]

I was just worried because the bigger fan leaves were somewhat shiny and darker green so i dropped to 400 ppm. Going to feed at 600 this time and see what happens. My fan leaves were more flat in the beginning but now they look like they're sort of cupping downward. The new growth looks like there are light green spots whch makes me think i need to up my ratio of Cal-Mag.

Yes up the Cal-mag. Looks like they need Mag specifically.

 

[MisterJones]

I get learning coco can be a bit tricky at first. What are you feeding them, pH, how often, how much run off? Are you supplying calMg with each feeding? If anything you might need to give them a bit more Mg. Don't see any N toxicity.

I've used Mother Earth coco for a couple of runs now, and haven't pre buffered, but the plants do get calMg with every feeding. Here are a couple of good resources:

I am using Gen Hydro nutrients FloraSeries, Cal-mag, and rapid start. I ph to around 6.2 and water usually every 3 days or whenever first inch is dry. I always do a minimum of 30% runoff and sometimes more. The chart says 550-700 ppm for early growth and 600-900 for late growth. Im thinking 700 ppm would be a good number.

 

[MisterJones]

Here is my feed chart for what i just fed the plant. There is the in and out values for ppm and ph.

 

[Aqua Man]

I'm a coco noob but here are my thoughts.

Most cal mag has a far to high ratio of calcium to magnesium IMO. Especially under LED (speculation) i feel it creates most of the cal mag issues we see. High amounts of calcium can also affect uptake of other nutrients as we increase the cal mag to fix what we see as a cal mag issue. Specifically potassium, phosphorus, nitrogen, magnesium and many micros. I combat this by using half dose of calmag and adding 1 gram per gal of epsom salt to bring th calcium and magnesium ratios to a more favorable level. I like Ca to be about half the ppm of my potassium and magnesium to be about half the ppm of calcium.

As for coco I feed at a volume thats 5% of the pot its in and look for 10-20% of that to come out as runoff volume. I adjust my feed frequency based on the runoff. If getting less than 10% i increase the frequency and water more often. This helps keep stable ratios, ppm and PH in the media.

I also use VPD as a guide for humidity and make sure I have good airflow through the plants. I like to keep room temps with LED about 80-85f with the lights on as this gives me my desired leaf temps of about 77-80f because I run co2. If not then maybe a few degrees cooler like 80-82f for 75-77f leaf temps. Then adjust the humidity.

Its important to co keep coco saturated to keep stable parameters in the rootzone.

 

[MisterJones]

I'm a coco noob but here are my thoughts.

Most cal mag has a far to high ratio of calcium to magnesium IMO. Especially under LED (speculation) i feel it creates most of the cal mag issues we see. High amounts of calcium can also affect uptake of other nutrients as we increase the cal mag to fix what we see as a cal mag issue. Specifically potassium, phosphorus, nitrogen, magnesium and many micros. I combat this by using half dose of calmag and adding 1 gram per gal of epsom salt to bring th calcium and magnesium ratios to a more favorable level. I like Ca to be about half the ppm of my potassium and magnesium to be about half the ppm of calcium.

As for coco I feed at a volume thats 5% of the pot its in and look for 10-20% of that to come out as runoff volume. I adjust my feed frequency based on the runoff. If getting less than 10% i increase the frequency and water more often. This helps keep stable ratios, ppm and PH in the media.

I also use VPD as a guide for humidity and make sure I have good airflow through the plants. I like to keep room temps with LED about 80-85f with the lights on as this gives me my desired leaf temps of about 77-80f because I run co2. If not then maybe a few degrees cooler like 80-82f for 75-77f leaf temps. Then adjust the humidity.

Its important to co keep coco saturated to keep stable parameters in the rootzone.

If you were to adjust my particular ratios for my most recent feed and add in epsom salt, how would you adjust it?

 

[Aqua Man]

If you were to adjust my particular ratios for my most recent feed and add in epsom salt, how would you adjust it?

What brand of cal mag are you using? And whats the ppm of the source water?

 

[MisterJones]

What brand of cal mag are you using? And whats the ppm of the source water?

I use zero water filters to get my hose water to basically 0 ppm. All my nutrients are general hydroponics .

 

[Aqua Man]

I use zero water filters to get my hose water to basically 0 ppm. All my nutrients are general hydroponics .

You may want to look at adding a ph buffer to that. I would say your PH will be unstable and can easily be changed by the simple uptake of nutrients by the plant. I'll link a thread that explains it in more depth. You water source will be that of distilled or RO water for reference in that thread.

In terms of cal mag use 1/2tsp per gal and add 1 gram per gal of epsom salt.

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www.thcfarmer.com

 

[Aqua Man]

Your temps and humidity look good but I feel you could run a bit warmer. I would get the pots up off the floor. You may want to check the lighting.

Are you on 18/6?

 

[Beachwalker]

I ... water usually every 3 days or whenever first inch is dry.

Water daily for best results, good luck

 

[MisterJones]

Your temps and humidity look good but I feel you could run a bit warmer. I would get the pots up off the floor. You may want to check the lighting.

Are you on 18/6?

yes i am using the 18/6 schedule.

 

[Aqua Man]

yes i am using the 18/6 schedule.

Of you download light meter by my mobile tools dev and test the lux i would say about 15-20k should be plenty at this point. Probably closer to 15.

As @Beachwalker pointed out you need to water a LOT more often.