After thinking that I did something horribly wrong, I've realized that the brown spots on my plants were just algae, which I removed most of. (Some left permanent brown spots, or the plant was going to reach that stage regardless) I'm noticing that even after a week, I have noticeable algae growth on the walls of the aquarium, and slowly on the plants now, as well. While I do not have exact water measurements right now, he's what I can name:
38g, Top Fin 60 filter
Water is kept at 76F
12x Neon Tetra
6x Cherry Barb
6x Bloodfin Tetra
I never added more than 6 a week, and the tank is only 80~% stocked according to AqAdvisor.
I forget the exact light model I have, but I made a previous thread and it was suitable. I keep it on for about 8-10 hours a day. My tank is near a window, which the blinds are always up. I do have room darkening ones that can make the room eliminate all sun, if natural sun is the problem here.
Lastly, I use ecocomplete and Seachems flourish. The problem is I threw out the bottle for the Seachems, and moved it to something new (pouring out if the Seachem's lid is a pain) and I remember dosing a half cap twice a week, for my 38g.
Any red flags? Is this a new tank issue? Do I need some substrate fish? Thanks!