I bought a cluster of hornwort when I set up the tank and poked it in the gravel. It grew well, then after a couple weeks began to brown on the old growth. The new growth looked healthy so I wasn't too concerned, but I read that it may do better floating so it can get more light. So at next water change, I pulled it up. That cluster had spread roots over about half my tank! I'm reading that perhaps it wasn't hornwort because of the roots. Anyway, seeing my mistake, I tried to replant it. It has continued to brown to almost completely brown and now the new growth has died off. It is not really dropping leaves. It almost looks like something is eating the new growth. My tank is low light and high pH. At this point I've pulled it up again and have it floating in a clear acrylic container on a covered porch for better light intensity. Also perhaps of importance, I'm starting to see some brown algae on the gravel. I'm taking this as a good sign that my tank is trying to establish an ecosystem. I'm not sure if that contributed to the plant's demise. Any ideas on what's going on? My newbie guess us that my hornwort is actually something else that requires more light and/or lower pH to live. And if there's no hope for this, to what plant should I look to replace it? My daughter saw some kind of moss balls at the lfs that she's interested in.