Growing indoor in Coco with Well water, how do I gauge my EC?

Quick question everyone, I'm unsure how to gauge my EC, I am growing in coco indoors, in a new spot that has well water.
The baseline EC a .6 before adding nutrients, so i'm not sure how many nutrients to add, as I don't want to overwhelm the plants with too many total dissolved solids.

IF MY target EC would be at a 1.8 (if I was growing in RO Water)
Does that mean I would add 1.8 worth of nutes + 0.6 EC of water = 2.4 total EC? Is that too high?

I'm wondering if the high-level's of calcium in the well water are interfering with the phosphorus uptake, as my plants are showing signs of phosphorus deficiency and I'm not sure if I am
1. not giving them enough nutrients, or
2. The high calcium is interfering with the phosphorus uptake

Growing both a mix of some Sativas & Indicas. 3 gallon Coco Botanicare moisture mix. Hand watering Drain to waste. Growth science nutrients. Inoculating with mykos.

2.4 sounds way too high...0.6 + 1.8 is 2.4


What pH are you running ?


As a general rule, for years I ran well water in a very high calcium area.... Both Canna and GHE head 6/9 recipe work well at around 2ml a/b (or equivalent with 6/9) per liter of water. Some Sativa dom plants went a bit dark, were better on 1.7... some indoor nute monsters were a bit pale and needed 2.4ml/L. I have always preferred to go light on nutes and not flush.

Start low and work your way up, the plants will tell you whats up.

Hi thank you for the replies. Yes I thought 2.4 For was too high as well. The highest I did was bump the nutes up to a 2.1 to see if there was any improvement, and there was none, they still seem to be showing Pale leaves and signs of phosphorus deficiency. I will be flushing today and backing the nutrients back down. I'm running my pH at 6, 6.1

I'm used to running Coco in RO water, so this is really tricky for me. The baseline EC of 0.6 is really throwing off my math. What do you think should be the highest EC I should go for?

Vintage1969 said:

Hi thank you for the replies. Yes I thought 2.4 For was too high as well. The highest I did was bump the nutes up to a 2.1 to see if there was any improvement, and there was none, they still seem to be showing Pale leaves and signs of phosphorus deficiency. I will be flushing today and backing the nutrients back down. I'm running my pH at 6, 6.1

I'm used to running Coco in RO water, so this is really tricky for me. The baseline EC of 0.6 is really throwing off my math. What do you think should be the highest EC I should go for?

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.6 EC is on the high side IMO. I would cut the well water with RO to EC of .15 to .2. 80 -100PPM on a 500 scale conversion like Hanna.

I then would include the base water in the total EC of solution. I never go above 1.8 EC. I have been finding I can go with .9 EC watering twice a day. Straight coco DTW.

I would do the RO well water mix and start at EC .9 and work up if needed. PH 5.8 - 6.0.

By the way, I'm of vintage 69 and lived in Santa Cruz.

All the water here I use is 0.8 and there have been no problems with GHE or Canna

The Growth Science nutes you are using are specifically for Coco ? If not, there is your problem. Read up about other GS grows, it may be that it is something up, your pH is fine... is hte water standing, do you check it before watering ?

ChaosCatalunya said:

All the water here I use is 0.8 and there have been no problems with GHE or Canna

The Growth Science nutes you are using are specifically for Coco ? If not, there is your problem. Read up about other GS grows, it may be that it is something up, your pH is fine... is hte water standing, do you check it before watering ?

Click to expand...

Damn So if your water is a 0.8, what is the maximum EC you water at? I always check my pH before watering, i usually water at a6.0, 6.1