Target EC question for DTW in coco

If one was following Dr. MJ Coco's nutrient plan, and the target EC is 1200, but it comes out to say 850 due to low starting EC of water, is that a good thing or should less water be used to bring EC up to target?

BoSwift said:

If one was following Dr. MJ Coco's nutrient plan, and the target EC is 1200, but it comes out to say 850 due to low starting EC of water, is that a good thing or should less water be used to bring EC up to target?

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Dr Coco's guidelines are based off of low or 0 EC water. If the EC runoff is consistently low, then it could be uneven distribution of water when you feed. Attempting to cause salts to crystalize out of solution to raise your runoff EC is not something you want to do.

How long as the EC runoff been lower than inflow and how do the plants look?

I rarely go over 1.2 EC, or 600 ppm's.
That's using tap water.

MickFoster said:

I rarely go over 1.2 EC, or 600 ppm's.
That's using tap water.

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Likewise, though I use RO water because the EC of my tap is 0.9 EC. What's the EC of your tap?

ec121 said:

Dr Coco's guidelines are based off of low or 0 EC water. If the EC runoff is consistently low, then it could be uneven distribution of water when you feed. Attempting to cause salts to crystalize out of solution to raise your runoff EC is not something you want to do.

How long as the EC runoff been lower than inflow and how do the plants look?

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These are 20 days from sprouting from seed. I stunted them by not understanding how to water in coco and assuming they needed no feeding at all until about a week ago but they look healthy to me for the most part. First grow for me... I actually haven't tested runoff EC. Not sure how to collect it. the 850 EC is from the gallon of feed solution. Is the target EC on the feed chart not for the solution?

This is what they looked like on the 18th, just 7 days ago before I started feeding and watering to runoff daily

ec121 said:

Likewise, though I use RO water because the EC of my tap is 0.9 EC. What's the EC of your tap?

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Around 0.4.

BoSwift said:

These are 20 days from sprouting from seed. I stunted them by not understanding how to water in coco and assuming they needed no feeding at all until about a week ago but they look healthy to me for the most part. First grow for me... I actually haven't tested runoff EC. Not sure how to collect it. the 850 EC is from the gallon of feed solution. Is the target EC on the feed chart not for the solution?

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Oh, I see. What you're saying is you're following his feed chart in ml's and the EC is coming out to 0.85 instead of 1.2. What you need to do is either keep the ratios the same and use more nutes, or use the same amount as you were before and use less water. If the EC comes out too high, then add in some water until you hit the target EC.

For runoff EC, however you get rid of the runoff, dump it into a cup and measure the EC before you discard it.

What nutrient parts are you using? Also, wtf coco mix did you use?

ec121 said:

Oh, I see. What you're saying is you're following his feed chart in ml's and the EC is coming out to 0.85 instead of 1.2. What you need to do is either keep the ratios the same and use more nutes, or use the same amount as you were before and use less water. If the EC comes out too high, then add in some water until you hit the target EC.

For runoff EC, however you get rid of the runoff, dump it into a cup and measure the EC before you discard it.

What nutrient parts are you using? Also, wtf coco mix did you use?

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Gotcha...
lol, I used Canna Coco and added perlite and some worm castings. 60% coco / 20% perlite / 10% castings. Figured the castings would help the seedlings... granted idk wtf I'm doing.
Using his mid veg portion of chart, flora series ( micro, grow and bloom ) with cal mag and some silica

BoSwift said:

Gotcha...
lol, I used Canna Coco and added perlite and some worm castings. 60% coco / 20% perlite / 10% castings. Figured the castings would help the seedlings... granted idk wtf I'm doing.
Using his mid veg portion of chart, flora series ( micro, grow and bloom ) with cal mag and some silica

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Okay, you're using like #4 perlite. Yeah, best to just use 70/30 to 50/50 coco perlite. You don't want any dry amendments.

Since you're only using micro, grow, bloom for the base, then the ratios (ratios, not ml's) you should use are:

Seedling & mild veg: 1/1/1 M/G/B
Aggressive veg: 2/3/1 M/G/B
Flower: 2/1/3 M/G/B

So the order would go, silica first and then let it bond with the water for at least an hour. Calmag. Then the 3-part, mixing between each part.

In this way, if you need to change the EC, you change it while keeping the ratios the same. So a 2/1/3 could be 3/1.5/4.5 in ml's if the EC calls for it. So long as the GH ratios are adhered to, you'll be fine if you bring the EC to the appropriate range for the stage the plant is in.