I have a 55 gal. fresh water tank, and now I want to get another tank, a much larger tank. The way I clean the tank I have now is to take out about 45% of the water and replace with clean water. This way of doing the cleaning would seem to me to be very hard to do with a much larger, is their a better way? I have asked the people at Pet Smart by my house and they are not of much use. I am going to make the new larger take a community tank, and the 55 gal. tank I have, I will put a couple of Oscars in it or something. Thanks for any help you can give.