Wow those are pretty similar! Other than the longer lighting schedule I see you are doing the water changes every week whereas I do it every two. This is mostly due to time constraints in my schedule but also because the water and overall cleanliness of the tank look fine on that second week. I could try doing it every week for a few weeks and see if there's any improvement.
Other than that, I'll definitely up the lighting from 6hrs back to 8, I'm also going to cut out some of the red tiger lotus leaves that are blocking light to some of the melon sword leaves. I'll also look into some macro ferts to supplement what the plants are not currently getting.