question about tap water ec

flodas

Well-Known Member
Gooday i have 10 girls that are in earlie veg. My tap water is 0.4 ec what i have read the optimum feed ec water should be 0.6 to 0.9 in this part of vet.

My question is if i should include or exclude the 0.4 background water in the final feeding solution that should be 0.6 0.9? / flodas
 

since1991

Well-Known Member
Add your nutrient ec on top of tap ec. Say your shooting for a target ec of 1.3 then your final should be 1.7. A 0.4 start ec is pretty decent if its largely comprised of calcium and magnesium carbonates. Should be good to go. Mine is 0.2. I like a 1.5 target in peak grow or peak bloom so my final is almost always 1.7 give or take a few points depending on strain, temps, carbon dioxide and relative humidity levels in the rooms.
 

MisterBlah

Well-Known Member
First thing you should do is get your water tested.

Do a google search for water testing labs near you. You should be able to find one that will test your water for $40-60.

Once you get the results back, I'd be happy to discuss what they mean with you.
 

churchhaze

Well-Known Member
While what @MisterBlah is saying about getting your water tested is true, you can pretty much assume that your water has mostly calcium carbonate unless it goes through a water softener.

In the case that you're not using a water softener, include the 0.4EC as part of your nutrients. Calcium is a nutrient. Try not to use water that's gone through a water softener as sodium will antagonize K and other positively charged ions.
 

churchhaze

Well-Known Member
I'm assuming you're growing hydroponically since you're talking about EC after adding nutrients.

Here is a trick to dealing with hard water.. Get a pH down based on nitric acid like technaflora's pH down. After adding your nutrients, figure out how much of that pH down you need to get to 5.8pH and remember that number. The next time you change your nutrients, use that recorded amount of nitric acid based pH down before adding the nutrients, then add the nutrients.

The nitric acid will react with the calcium carbonate in the water to make calcium nitrate, which is a macro salt. The carbonate will leave the solution as CO2 gas.
 

MisterBlah

Well-Known Member
I'm assuming you're growing hydroponically since you're talking about EC after adding nutrients.

Here is a trick to dealing with hard water.. Get a pH down based on nitric acid like technaflora's pH down. After adding your nutrients, figure out how much of that pH down you need to get to 5.8pH and remember that number. The next time you change your nutrients, use that recorded amount of nitric acid based pH down before adding the nutrients, then add the nutrients.

The nitric acid will react with the calcium carbonate in the water to make calcium nitrate, which is a macro salt. The carbonate will leave the solution as CO2 gas.
Just buy Nitric acid. You can buy 70% Nitric acid for $35/L. It will ultimately be cheaper than the 5-10% solution of the technaflora product.
 
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