Just got an EC meter and the tap water reads 0.90! I am starting my first aero-hydro culture and from the research i have done i know that i should start with 0.5 and end the harvest at 2, 2.5 Now if i don't use a water filter how to adjust the solution should i start with 1.4 and end at 3.4!!!!!!!! Or just how does it work? Thanks!
If you are using unfiltered tap water then you need to let it sit overnight first to clear the chlorine. Adding 60 ml/100 L of H2O2 is recommended to oxidize any creepies in your water. Whatever the EC value of water reads is pretty much irrevelant when mixing ferts. You can only add your fert to the desired value including the contamination. Using pure water will allow you to add more food since you removed the contamination factor. Now I said the EC value is irrevelant when mixing the fert that doesn't mean it is insignificant. Contact your local water authorities and ask them general questions to what the impurities of the tap water is and at what quantities. Adjust your fert recipe to account for those minerals and you should be ok.
