Mommies dont look so good

Left my moms for a couple days and saw some yellowing and edge burn?
Sour Diesel
Canna Aqua Veg A&B
H2O2 at 1.5 tsp per gallon
1 tbsp epsom salt per 20 gal
20 gallon rez
Flood & Drain cabinet
400w MH
Temp consistently 76 - 80 deg.
650 +/- PPM
5.7 ph
Diced rockwool/hydroton mix
Flooding once daily for 15 min

Any clues on how to correct? Maybe too much rockwool in the mix? These are 3 weeks from tiny clones.

Nute burn, drop back to about 400.

Your ppm is high ...and only use one nut right now

That is a great example of nutrient burn...starting from the lower leaves...yellowing of the tips...excellent to show nutrient burn...and do what buds said...dial it back...increase it again in another week to 1.5 weeks

Will do. Thanks folks. Really did not think I was too high at this point, but will dial it back for a bit and see if it corrects. LOVE RIU!