Floating for 10 minutes will surely kill them! That's not the floating method.
This is how you do it:
1. Turn off the aquarium lights and dim the lights in the room.
2. Float the bag containing livestock.
3. After 5 minutes, cut the top off of the bag and add half a cup of water from the aquarium. To prevent the bag from sinking, roll the edges down on the top of the bag (after cutting off the top).
4. Repeat step 3 every 5 minutes until the bag is full.
5. Once bag is full, discard half of the water out of the bag (do not dump water into aquarium, get rid of it).
6. Repeat step 4 and 5 until bag is full again, and then NET livestock from the bag.
(7.) Make sure with sensitive invertebrates such as sea stars, sponges, cucumbers, and anemones that they don't touch air. This can be fatal for them.