Do you kow what the name of the plant is?
I ask because it looks very similar to cyperus helferi which turns brown when it acclimates and when it is not happy. I started with about 6 clumps of cyperus helferi in my 10g and I probably have about 2 actually clumps left. I wasn't able to get it to grow in a clump so I separated by rosette and then planted it. After a few weeks I was finally able to get new growth. Also they are root feeders so you'll need a good root tab under them which really helps get new growth. I should also tell you that c. Helferi do not like to be moved too much. I lost some every time I moved them so I put them in and left them. There's not a ton of info on C. Helferi on the internet so your best bet if that's what it indeed is, is to ask on here. I know of one other person besides myself on here who has them and I do believe their's are doing well.
Sent from my SAMSUNG-SM-G900A using Aquarium Advice mobile app