I have a 4' tank that I've just finished the initial planting on and have started cycling for fish. I am going for a low-med light setup, dosing TPN+ and EasyCarbo with a substrate of TetraComplete topped with Eco Complete. I am very happy with how everything looks at the moment, except for the centre middle. Because I have quite a thin layer of 'plantable' substrate at the back in the center, it's tricky working out how to plant it to get decent coverage. I've got the one Aponogeton at the centre that will need to come out, as it looks pretty awful and didn't really survive transit. Can I have any suggestions for suitable plants at the back there? Thanks.