Your Bolbitis should get new sturdier fronds with the good light you're providing, the old ones will remain floppy until you trim them off in favor of newer growth. There is nothing wrong with the floppy fronds though, it's the result of the conditions it was grown in. I don't see any signs of damage or algae so it should do fine once it has adjusted to the new conditions. Do you have it in an area with good flow? Mine always do best when I put them in an area with a lot of water movement.