I don't know if this is beneficial or not but I'm a lazy type person and this is a way I've found I prefer to do my water changes. I have a 5 gallon tank and I do about 50% twice a week. I kept getting water all around my desk (not good with my own and my roommates laptops around) so to cut down on the mess this is how I've started doing my water changes. I use 4 empty 1 gallon spring water jugs for this. I fill 2 with tap water and give the appropriate treatments for 1 gallon in each and then leave the other two empty. I use a spare length of airline tubing to siphon out the water into the jugs, and then reverse it when adding the other two clean gallons back. I've found that this keeps me from making such a big mess, and I also don't have to remove my fish to do it this way. I've noticed this doesn't stress my fish, it may take longer but for me is a much cleaner way =P