Moss - Spiky (Taxophyllum sp.)

Spiky Moss is a variant very similar to Java moss, however has a slightly different appearance and texture in the leaves. In terms of growth habit, it grows very similar to its more popular cousin Java moss. 

Even better, it can attach to gravel or substrates which has the added benefit of keeping it from circulating with the water currents in your tank.

In addition, it will attach itself to almost anything in your tank that sits still for long enough, including commercial decorations, rocks, and driftwood.