Hello! So I have a ten gallon tank now, but I have a 20g long tank to set up when I move in just a few days now. I bought some regular aquarium sand to put in the 20g tank (I'm currently using a mixture of marbles and small stones) because I have heard that sand is more beneficial to bottom feeders, and I have two corydoras. (Please don't tell me I need more than two. I'm well aware that they are schooling fish, and I had three but one died and I wanted to wait until I move to add more fish). Anyway, I've heard from a lot of places that sand needs to be rinsed prior to adding to a new tank, but I've also heard you do not need to rinse it. So which is it? I have a betta and the two corys I had mentioned before, if that helps at all. A prompt response would be greatly appreciated.