A pic of a leaf taken under LED light with no more info than you've given, makes it impossible to make a call. Take pic of whole plant, especially new growth...since that's what you judge the overall health of your plant by, under NATURAL lighting (no LED purple) and repost. From what I see on this leaf, nothing is wrong with your plant and that looks nothing like a magnesium/calcium deficiency to me. Also, give information about how you're tending the plant...when you water, any nutes given, grow media, etc. The more info we have, the easier it is to make a call. TWW
check new pics. 5gallom Dwc advanced nutrients jungle juice 1tsp per base nute, micro first , then phd to 5.5. I put in fresh tap water with a little bit of micro last night but just got some fresh ro water in today phd to 6.
Get some calimagic. You have both magnesium and calcium deficiency it looks like. The light green bands on the upper leaves like stripes are mag deficiency. Brown/Yellow spotting is calcium. If you want to stick with Advanced Nutrients get some Sensi Cal-Mag Xtra.