brown/purple/rust colored spots on my 2 week seedling

So this is my first grow but I have been reading and learning the past 2 months or so soooo im not quite in the dark. Today is day 14 for my a.k. seedling and im loosing my first two leaves to what appears to be either a calcium or mag defic. Possibly due to low seedling temps... but not too likely. I do use distilled water which supports cal/mag def. Here is what i gots goin down.
Light-250w cfl blue spec 8" from plant give or take a couple inches.
24 hour veg
Ph-5.5 to 6.0 (im using drop test so its hard to be accurate. Ph pen comes soon)
Fox farm big grow hydro nutes. Ppm 145 for n
Settup is a dwc with 4 good size airstones. With "breathe" natural co2 next to my air pumps
Temps stay from 68-75 give or take a degree or two. Normally around 72 right at the plant.
Great vent with a big inline in a 3x3 tent.
Suggestions??? I think im going to buy cal/mag today and add at 1/4 strength
concerns? Advice? Help im gunna loose her!
Ok this sucks now i can't attach files so if someone needs pics ill send them via email. Pleaseeeee help!

ok i have pictures now that i should be able to post. There are three pics. one is on day 9 (first day of def, showing) second is day 10, you can tell it is advancing fast, and with my plant so young it took a toll on the growth rate pretty bad, ill be 2 days behind or more if it shocked the plant bad. The third pic is almost 24 hours after adding cal/mag to the DWC (200ppm) and the nutes were upped to 345ppm. no sign of burn or def. I also cut off the two dammaged leaves. You can see in the last photo there is one more brown spot showing on my first set of leaves, im just hoping it stops here. I will keep a close eye on it. Again any suggestions questions or concerns feel free to pipe up!!Attachment 287298Attachment 287299Attachment 287300

this is the 9th and 10th and 11th of the month hahaha the day is actually day 13,14,15 from sprout.