SuperColey1
Planted Section
i'll try and take some pics tonight of the plants. the plant is going brown i could not find on the link you posted. (they are all for fresh water tanks). looking again they very similar to the ones on the right of your tank at the back in your first pics.
Tropical is freshwater
Check on this one to see if it is non aquatic:
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The plant at the back right is a Java fern. If yours is one of these it would take months to go totally brown!! Its one of the recognised 'hard to kill' plants. in that even thuogh sometimes it starts deteriorating getting holey and getting brown bits it keeps plugging away and putting out new leaves and 'plantlets'
AC