In my experience, usually a metallic taste is too much iron.
Were you using well water? If so, did you have it tested?

No well water, just plain old municipal tap. Water is all within EPA standards so highly doubtful that its the extra iron in the tap water. For the initial growth phase I was using Dyna-Gro Grow nutrients and at pretty high concentrations, not sure if that formulation was intended for vegetables (human consumption). Strangely I had the same nutrients in my DWC strawberries and DWC tomatoes but they came out tasting great, go figure.