I learned that you must be careful when removing airline tubing from an aquarium. I had left a section of the tubing in the tank overnight as I was still adding water back to the tank after a large water change. When I pulled the tubing out, I saw (what I thought) was a plant leaf stuck to the tubing. Since I had done a lot of moving of plants, trimming, and added a few new specimens, I didn't think much of it. It is a good thing one of my cats distracted me for a moment, because when I turned back to the tank to take the tubing out, my Farlowella was 'crawling' backwards down the tube to return to the water. It is amazing how they can use their fins to almost walk like legs.