I have a 10 gallon tank with a betta, 2 swordtails, and 6 neon tetras (please don't start freaking out that it is overcrowded, it's not believe me). Anyways, I have been cautious about my water changes because I have learned the hard way that they need the tank to be cycled for tetras, they are delicate little things! So I have been doing about 25% water changes every 4 or 5 days. I finally decided that I was going to use the syphon (gravel vacuum? I don't know exactly what they are called) to do a 50% water change. I didnt want to suck those tiny fish up so I emptied some water from the tank into a bowl and got the other fish out then got 1 tetra in but he went belly-up as soon as he got in there! The others did the same! They weren't out of the water long. BUT, as soon as I put them back in their regular thank, they came back to life! Weird eh? So my questions is- How do I do a water change? I need to vacuum and clean the gravel really bad! Sorry for the novel and thanks for the help! I need it pretty urgently!