Appears to be cal/mag issue. You say no nutes as of yet, what kind of soil are you in? Most store bought potting soils have nutes in them already. What are you using to water? (Tap, distilled, RO?) Distilled and RO have no minerals in them and will cause cal/mag issues in many cases. try a tbsp of Epsom salts next water and look at the new growth. If those edges are crispy they're gone, but the plant will survive. Lock outs are caused either by pH or an overabundance of another nutrient. I doubt it's that. could be wrong tho........It's been known to happen