I think it's too late to worry now, but in the future you can try adding some calmag supplement will give her the magnesium and calcium you don't get in some water sources.
@Cnk671, i just saw your setup... I'm sure you'll do fine... My only advice is not to overthink and just let it grow... That's what I did... I don't have much equipment yet... Light, tent, nutrients and a loupe... Let her dry out a bit between waterings..
@Wicked_Stix, well I flushed it with 10 litres of water yesterday, maybe it lowered the pH... I'll try to feed again next watering and see if it moves..
Thank you so much for answering my question...