Starting with the substrate, how deep is it now? I can't tell from the photos but it seems fairly shallow. For planted tanks you will want about 2 to 3 inches overall depth (meaning, 2-3 inches when level throughout the tank before you arrange it with slightly more in the back and slightly less in the front). And at this point, you might want to consider a different sand; pure white is not the best for fish, and it makes viewing the tank harder for us because of the glare. I have play sand in six of seven tanks; it is very inexpensive, natural in appearance (replicates sands in the Amazon) and works well for fish and plants. Now is the time to change rather than later.
As for wood or rock, this largely depends upon the needs of the intended fish. Providing an aquascape that resembles the fish's natural environment will always be a benefit, as the fish will be more settled and more likely to exhibit natural colours and behaviours. Most fish we keep come from creeks and streams with wood (chunks representing fallen tree trunks, branches, roots) so this usually fits in; fish like pleco must have wood to graze as part of their digestive process. I like the Malaysian Driftwood which is very dark brown and heavy so it sinks immediately, and you can get chunks with crevices and tunnels that are ideal for many substrate fish. Some habitats have rocks, some don't; some fish won't care, as long as the rock is smooth and not sharp edged.
Dry leaves (oak, beech, maple) are a nice addition, and now being autumn you can collect some that have fallen from the trees (select an area away from traffic and possible pollution); once waterlogged again, they will settled and lay on the sand. Fish love to graze these for microscopic food, and again they are a natural part of most tropical habitats.
If you do decide to change the sand, I would remove the fish to a temporary holding tank. It is always wise to have an empty spare tank around for emergencies, and a 20g is what I suggest. You can use the filter and heater from the existing tank in the temporary while it is in use for this. I or others can detail the process.
As for plants, there are many that would likely work. What is the lighting? And what are your water parameters (GH or general hardness and pH) of the tap water?
Byron.
I would like a guide I suppose and suggestions.
