Good morning Zoe,
It's good to see you have new growth on all of your plants so things are going in right direction. Those Diatoms will surely disappear before long and I know some will say to just leave it but I can't help thinking some of those Anubias leaves would benefit from a light rub between the fingers. I would also try and keep clean that area right at the front where the substrate meets the water column, it gets a lot of light, direct from lamp, ambient light and refracted light (think that's the correct word) that travels down in the glass and can become an ideal breeding ground for Cyano or some form of algae. Obviously, if were to do this do it just before a water change.