That's low enough. One of the main things to watch for is ph rising....which it will in nuteburned plants.....quickly. The other thing is watch your ppms....if the number rises keep adding ph correct water to dilute it. The plants may drink alot of water right now and leave the nutes behind.....they already have too many on board....so you need to watch it carefully.

Buzz.....they look pretty chewed. The only thing you can really hope for is healthy new growth....those leaves aren't going to improve so keep an eye out for any sigsn of NEW growth. They honestly look pretty sick to me.

Good Luck.