Originally Posted by Emerald Terror
Ill try rubbing it off at home. Do you know what plant the large one is because the smaller ones are just runners? Do you think the brown on the larger plant is bad?
The species is Echinodorus bleherae, it is the most common "amazon sword" plant and a very lovely plant too.
The brown on the larger is fine, that was from the past. Now, as this plant adjusts, new leaves will appear from the centre of the crown, and the older existing leaves will all slowly yellow. Leave them for the present, until there are several new leaves that are fairly large, at which point you can remove the yellowing ones.
Some nutrients are what we term mobile; these will move within the plant, as from dying leaves to new leaves, so the new leaf is better fed with that nutrient. As these plants are newly introduced, it is best to leave the yellowing leaves (when they occur) for a time so the plant benefits from the mobile nutrients stored in those leaves.
Something else that really helps this species are substrate tabs, such as Seachem's Flourish Tabs. Just one inserted into the substrate an inch or two from the plant crown will last 3 months and provide additional nutrients to the roots. Echinodorus plants are heavy feeders, meaning they use a lot of nutrients compared to some other plants. Not essential, but you will see a difference.