I did my little DIY out of necessity. My 7 year old came home with a cray and I had no tank set up for it. I took an extra 10 gal that was empty. Pulled a couple of the pot scrubbers out of one of my established filters and made do. I live about 30 minutes from the nearest Walmart and at least an hour from the nearest LFS, so going out and buying a filter just wasn't possible at the time. I found that it works quite well. Now I know that if I need a QT or a hospital tank all I have to do is grab a cup stuff it with established pot scrubbers and I have an instant cycled tank. I don't have to leave one up.