E.C and hydro

A2Michigan

Well-Known Member
I’m using a recirculating hydro system and I’m trying to figure out how I can tell if I’m feeding too heavy or too light based off of E.C. I’m currently in flower and I think I have a potassium deficiency. My 55 gallon resevoir is at an e.c of 2.3, ph is 5.7. After 24 hours, I check the water level and I see that the water level has dropped and the ph is roughly still the same but the nutrient strength is stronger. 24 hours ago, the nutrient level was a 2.54 ec. Today before adding water to the resevoir it was 2.64.

1. Should ec be dropping or rising if I check on the resevoir 24 hours later and notice that the water level has dropped? the loss of water creates a higher nutrient concentration, correct?
 

myke

Well-Known Member
Yeah I’ve seen this chart and I’m trying to figure out if you are suppose to measure the ec before or after adding water to get the water level back up
I think your over thinking it. Measure EC after top ups have sit for a bit.
 

A2Michigan

Well-Known Member
My ec always lowers after top ups because I’m adding water to dilute the nutrients… idk man I’m just confused. I was told the other day that I should be feeding at 3.0 ec.. that’s a lot different than 2.3 ec
 

redi jedi

Well-Known Member
3
My ec always lowers after top ups because I’m adding water to dilute the nutrients… idk man I’m just confused. I was told the other day that I should be feeding at 3.0 ec.. that’s a lot different than 2.3 ec
3 is pretty high but what do your plants look like?
 

MustGro

Well-Known Member
I’m using a recirculating hydro system and I’m trying to figure out how I can tell if I’m feeding too heavy or too light based off of E.C. I’m currently in flower and I think I have a potassium deficiency. My 55 gallon resevoir is at an e.c of 2.3, ph is 5.7. After 24 hours, I check the water level and I see that the water level has dropped and the ph is roughly still the same but the nutrient strength is stronger. 24 hours ago, the nutrient level was a 2.54 ec. Today before adding water to the resevoir it was 2.64.

1. Should ec be dropping or rising if I check on the resevoir 24 hours later and notice that the water level has dropped? the loss of water creates a higher nutrient concentration, correct?
In my system (40 gal) I get very little change in EC when they’re small or right after a transplant. They will take up fluids and maybe a little bit of nutes, but they often get yellow lowers from using their stored nutes. After a week they get thirstier so the fluid level drops more quickly. The EC will drop here too and I use the fluid level to control the EC. If I top up the level every day I’ll lower the EC in the tank too quickly, so I usually let the level drop when they’re small as there is only .5-.6 EC in my tank now.
Big happy plants with great light and a dry atmosphere use fluids and EC. When they’re in say week 5 of flower, I’m topping up with 2 gallons first thing in the morning. Then I’ll do my EC and PH checks. On a good run I’ll top up 3 times a day because they’re hungry and thirsty and they’ll kill the EC in a tank in a week or less. Fine with me. I could mix stronger batches and get longer runs before the EC is too low; but it burns them up when it’s fresh and high EC. My PH usually bounces around the first day after a new tank, but after it stabilizes I can add 4 to 6 gals a day and it won’t need much adjusting.
I think you’re overthinking it like @myke said. Relax a bit.
I don’t know what nutes you’re using but the EC seems high and the plants look like they’re getting too hot a mix in general. To me anyway. I doubt you’d have a deficiency at the EC you’re running, but it’s possible.
Me personally, I’d mix more batches with a lower EC.
Any of that help you?
 
Last edited:

A2Michigan

Well-Known Member
In my system (40 gal) I get very little change in EC when they’re small or right after a transplant. They will take up fluids and maybe a little bit of nutes, but they often get yellow lowers from using their stored nutes. After a week they get thirstier so the fluid level drops more quickly. The EC will drop here too and I use the fluid level to control the EC. If I top up the level every day I’ll lower the EC in the tank too quickly, so I usually let the level drop when they’re small as there is only .5-.6 EC in my tank now.
Big happy plants with great light and a dry atmosphere use fluids and EC. When they’re in say week 5 of flower, I’m topping up with 2 gallons first thing in the morning. Then I’ll do my EC and PH checks. On a good run I’ll top up 3 times a day because they’re hungry and thirsty and they’ll kill the EC in a tank in a week or less. Fine with me. I could mix stronger batches and get longer runs before the EC is too low; but it burns them up when it’s fresh and high EC. My PH usually bounces around the first day after a new tank, but after it stabilizes I can add 4 to 6 gals a day and it won’t need much adjusting.
I think you’re overthinking it like @myke said. Relax a bit.
I don’t know what nutes your using but the EC seems high and the plants look like they’re getting too hot a mix in general. To me anyway. I doubt you’d have a deficiency at the EC you’re running, but it’s possible.
Me personally, I’d mix more batches with a lower EC.
Any of that help you?
I just entered week 4 of flower. So basically if you were in week 4, and every morning you check the water level and notice that it’s down you then add more water to correct the fluid level, right? At that point you then measure the ec of the resevoir and then do you top off with nutrients or just wait a week until they use up most of the nutrients? I think it could be that I’m flooding every 2 hours for 30 min, with 24 plants it takes about 30 min for them to get flooded and then they drain
 

MustGro

Well-Known Member
I just entered week 4 of flower. So basically if you were in week 4, and every morning you check the water level and notice that it’s down you then add more water to correct the fluid level, right? At that point you then measure the ec of the resevoir and then do you top off with nutrients or just wait a week until they use up most of the nutrients? I think it could be that I’m flooding every 2 hours for 30 min, with 24 plants it takes about 30 min for them to get flooded and then they drain
I never top off with nutes anymore. I’ve done it twice in the past when I was a GH grower and I always got sideways twisting leaves. All my top-ups are with .1 EC tap water at 7.5 PH (yeah I could drop the PH but I don’t bother). So yes, I wait a week, more or less, then dump and mix a new tank. I’ve never done ebb and flow so I can’t advise you on that part.
 

redi jedi

Well-Known Member
I just entered week 4 of flower. So basically if you were in week 4, and every morning you check the water level and notice that it’s down you then add more water to correct the fluid level, right? At that point you then measure the ec of the resevoir and then do you top off with nutrients or just wait a week until they use up most of the nutrients? I think it could be that I’m flooding every 2 hours for 30 min, with 24 plants it takes about 30 min for them to get flooded and then they drain
You could continually top off your res but its difficult to know the right amount of nutes to add back. Drain to waste solves that problem.
 
Top