Thats a Bolbitis Heteroclita at the back. My first time actually, it is a strange plant, on the edges of its leaves, towards its pointy end, shoots of roots are coming out. Curious about what are they going to be!
Filtration, with canister filter, ATMAN 3338, looks like the large EheimPros.
For the diffusion, Im using a glass bell diffuser, you can see it on the right side of the tank.
And about the background, Ive recently took it off, there was a blue background, left from the old times when there were frontosas in. I was thinking of putting the bacground after the glossos become more dominant. Just to be more complete with the glossos filled in. Black or white I was thinking, but black is probably the one
You said bigger plants? Where would you put them?