New pool and just added salt. 15million%???

I've never had a pool before. now I have a little over 18k gallon pool and it's a fresh fill. Running Pentair intelliflo and intellichlor and my pool hasn't had any chemicals added except salt yesterday. I put 400# of salt in and my screen logic numbers are confusing me this morning.
I don't know what other details you all might need so please go easy on me.