Dwarf Hairgrass

My guess would be the corys, I got Malaysian Trumpet Snails also and have hair grass also and n on of my grass was uprooted before. Try tying it down to a big rock or some thing thats heavy then bury it?
 
You mean rock wool and I think that's doable. I flipped through this beginner's guide to aquarium plants and it said that you should take the plants out of the pot, cut the rockwool into smaller pieces (so you have smaller bunches of plants) and then plant these into your substrate just enough to cover the rockwool
 
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