Zinc deficiency?

View attachment 2411722View attachment 2411723Hey everyone
I have 3 seedlings growing in a organic mg potting soil , no nutes. There almost 2 weeks old , grown from seeds. They seem to be doing very good, but I noticed on one that it had a blistery, sort of wrinkly appearance on the leaves, looks like its in between veins. It looks like it may be slightly yellowing . I think it may be a zinc deficiency but I'm not sure. What can it be????




I checked on it again tonight and it has spread upward to the newest leaves, but the bottom arent affected at all. Im starting to think it has something to do with ph of my tapwater - the water here is very hard, the kind that leaves the white stuff on the bottom of kettles.... I have a ph meter that has been reading a steady 7 ph, but its one of those ones withthe 2 metal probes you stick in the ground, and im starting to think the readings are BS. Ill be getting a digital meter , but until then ill be giving it drinking water....
 
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