I am a beginner!!!!!!!! I have a 2.5 gallon freshwater tank w/ 2 small zebras and a small angel. I have got the bug so i am now going to move up to a 20gal. I am ready for a H2O change and have several questions abouut changes and cycling. --I have heard that when doing an H2O change that you should change 50% and some say no more than 20%, which one is it? --When I do the H2O change can i put the H2O from the 2.5gal. tank into the new 20gal tank to help with cycling? --Can I put the old zebras in the new tank or get new ones? I don't want to shock and kill the old ones, since they are already used to the tank they are in. I know that it is recomended to have a school of 6, so would it be better if I put 4 new ones in the new tank and then add the other two? --When should the old fish be put into the new tank? And how much water should be taken out 0f the old tank and put into the new tank when the fish are moved? --I want to use the old tank for two betas with a devider, when i get ready to put them in, should i put in one at a time or both at the same time? and how much of the old H2O needs to be kept in the tank and how much new should be added. Thank you for all the time and info, it is really appreciated.