Are you using a root stim? there some great looking roots after looking over the thread I see you've had issues but not to worry they lookin good again now.
Just be sure it was chlorine and not the res temps etc good to see you decided to drop the ppms (i would go even lower to maybe 400/500 but I still don't know the deal with GN but i do feel strongly that nutes don't apply only ppms) in the long run I feel you are starting to get on the right track find the sweet spot and remember when she drinks water ppms go up.
All these bumps in the road will make you better at it in the long run believe me on that for that reason I would like to tell you she's going down hill to make you research more haha but in truth given the slime attack her recovery is great, I'm now at the point i can just throw things in the buckets knowing what roughly the ph and ppms already are,when you know what the mistakes are, you learn instinctively not to make em in the routine and throw perfect ressys together in mins . I prefer not to use h202 given the research I've done but that's a personal choice.
good work keep going