Fe maybe that's what I was thinkin ... Realistically it could be anything until we know if it's acidic or alkaline...forgot to add: nope, Zn is out, no symptom match at all there,... it's very distinct! --it is however, a very common micronutrient defc., along with Fe,... Mn is quite rare,...
...Guys, if you haven't seen it yet, check out the Defc. Pic Depot I put together here, in the sticky's section here, above the general postings section,...
You have a furnace? Use the condensation run off unless it's fixed to the drain pipe. Basicly distilled water@Waira
https://www.autoflower.org/threads/first-auto-indoor-grow.52101/
Link for the grow journal
I should add that my house has well water that has some iron and a bit of sulphur to it. I sometimes get em spring water and hit em with some of that