In 2016, I posted a list of tools that you should have in your fish keeping toolbox. Omitted from that list was a spring clamp….or five. They come in various sizes and materials. Some are metal, some are plastic, some are nylon, and some are a mix. Whether you maintain one tank or 100, you will find numerous uses for these, from clamping hoses to serving as a towel holder. In time, they will become almost indispensable to you. A bonus is that they are quite inexpensive. At last check, a dozen 3.5″ clamps was $7.99 on Amazon. Well worth the investment, IMO.