Ok, got everything figured out :) One of my roommates unintentionally threw away the bags with the subwassertang in them in the trash, I dug through it but couldn't find them D: There were two very small bunches that the snails took into my zen tank with them, however, so I tied them both to my zen temple decoration with some khaki thread I found in my emergency sewing kit XD It's the same color as the decoration. I really hope the subwassertang grows! I think the bits I found might have been just big enough to proliferate.
The microsword has been smushed down into submission too. It looks sad about it (can plants be sad? LOL), but the tank looks much better.