Java moss question

Java fern has a heavy, green rhizome but it also has thin roots. If that is not what you are seeing it sounds as if you might have algae?
 
Ah, then it sounds as if you have algae growing in your moss. Some type of algae eater might help: siamese aglae eater, otocinclus, Amano Shrimp, etc.
 
New growth on Java Moss in low light situations can be hair-like. Look at it with a good magnifier and see if it looks scaly - if so it is the moss and it will branch/bush out with time.

Large numbers of Amanos can reduce Java Moss back to thread-like appearance if the proportions of moss to shimp is too low. But again, the magnifier will show the difference.
 
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