I got several new plants for my *cycling* fish tank around 2 weeks ago. I purchased an amazon sword, vallisneria and hygrophila. They all started melting at first, but after a trim the amazon sword and vallisneria improved. The hygrophila however is still getting more brown leaves daily, I trim them off and then more start dying. There’s some whitish translucent fuzz growing on the dead leaves too. I did a hydrogen peroxide dip but that didn’t get all the fuzz off and leaves are still dying. I put some flourish tabs in to see if that’d help too. Is this normal? What could be causing this and how do I treat it? The plant looked fine in the store.