Can I fix this? Kinda looks bad.

looks like caclium and nitrogen problems... based on mulder's chart, it's probably 2 coinciding issues. need more of both. yellow tip-in and bottom-up - check == nitrogen deficiency spots with no interveinal chlorosis calcium deficiency. these don't have an antagonistic or synergistic realtionship, so they can definitely be coinciding with each other. (mulder's chart is dope AF .. )

Hello, Yeas is a calcium def because of the spots you can fix them by adding calcium, also the yellow leaves, if is only yellow for old leaves then is okay but yellow goes up to the new leaves so you need more nitrogen btw did you check your fish water PH? Enjoy

From what I've read in your diary, you gave the plant a flush. The flush removes most of the nutrients present in your medium so then you should go back to the feeding schedule. I couldn't find your nutrients but first use the 3-parter of micro, grow, bloom to get rid of most of your deficiencies. Then you might need to add a bit of cal-mag because I belive you have a calcium deficiency as well. Good luck with the rest of your grow

Start giving her some grow and bloom. Calmag if you've got it will help.