I didn't mean to add that pic, sorry about that. I fixed the ph about a week ago and it is still good 5.7, but you're exactly right. The ph was 4.2 and I adjusted it when I added water to dilute the solution and it worked ok. The pic from today, is the second one in the link. Can you look at that for me and tell me what you think? I'm pretty sure it is the same type of yellow tips I have seen in other threads that turned out to be nutrient burn, but I guess not sure enough that I can just go back to feeding it according to instructions, maybe it is just a residual effect of the low ph from last week?