Your Plant Question
Good morning Ruairi...
Amazon swords are typically low to medium light plants. If you're using the lighting that came with the tank, that's only for viewing the tank, not growing plants. Fish don't care about lighting, but your Swords need a 6500 K, T8 for tall tanks, T12 for a wider one.
Depending on the volume of your tank, a 17 watt bulb will work for a small 30 G and 32 to 40 watt for a larger 45 to 55 G tank. Much larger tanks will need multiple bulbs.
Large water changes of at least 50 percent weekly and some fish are needed to provide the plants with macro nutrients and you need to dose a commercial fert in dry, granule or liquid form for the micro nutrients.
Provide these for your Swords and they'll start to improve.
B