Step 1: Get moss
Step 2: Tie moss to something
Step 3: ???
Step 4: Beautiful underwater moss plains.
But the stuff comes in a clump. How does it ever become lovely waving grass fronds? Well after some trial and error, I may have figured it out.
Would have taken pics but no camera currently. And this is more fun anyway, right?
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Not pictured: Having a grid with tiny holes, and needing to jab them with a pair of scissors to make them big enough. But my persistence has been rewarded, and I have a very small and very lovely small grass-like test clump in my tank now.
Now all I need... is another hour or three of spare time to sit and stuff the rest of the moss through a plastic grid.