I have posted several times about my tank maintenance set-up. There are multiple advantages to using this process, which you can read at the end of that post.
Two of the advantages are money savings. One, of course, is that I don’t waste any source water in the effort, which is normal for Python-type vacuum systems. The other is that I recycle my sand. Yep, you can reuse the sand that you vacuumed out of the tank during your regular tank cleanings. How? It’s a bit work intensive, but you will save some money in the long run.