I just bought formula one frozen food, and when I thaw it, it is like a soft rubber cube and hard to feed. I was unable to break it in bit size pieces, so I then put it in a cup of water and smashed it then it was too small, and had leftovers in the tank. I then started a thread on the best way to feed it and someone gave me a great way to do it, with little work and best of all no leftovers in the tank. How you feed is, first, thaw it out. Second, run a piece of fishingline threw it and tie a knot on it. Finally, you hang it in the tank and let the fish eat it. One way I found to hang it is use that old bottle of horrable flake food and put the line in the cap. This method, so far, has worked great for me. I hope it can help someone else who uses this food. Good luck, and let me know if it works for you.