Mango Kush MediSeedMan

Hard to say with the age. If you have time/space I would keep growing to see what the next few sets of leaves look like, My only concern would be stunted growth from the mutation adding weeks to a grow. Some plants will grow out of a early mutation and produce just like a "normal" growing plant would. Happy growing.

Could be many of things from a virus, to a mutation. I have had the same thing on a few plants over the years. You do have a magnesium deficiency started. That or your ph is not right in substrate.