Its interesting to get so many different strategies used on our water friends! Whether we thaw out their food or just toss it in frozen? My preference is to thaw it, but by doing this I take the time to also sit and watch them eat. Only time I would throw frozen in would be if I was in a hurry and not taking the time to watch them. We learned the hard way that it is always best to take your time and watch closely. We lost a beautiful Queen Angel by being in a hurry one day. She grabbed a piece that she couldn't digest or swallow properly and she choked to death. This has happened twice now, earlier with another fish, so now we thaw and watch. Reason we know it choked, we saved one by doing a fishlick maneuvre! LOL. Sounds crazy, but it worked.