im getting a tunze 6060 from a friend that has let it sit for over a year. ive never used a tunze before. he told me i needed to order a propellar for it. im trying to look on your site for one. i guess im blind and cant find one. also do you think a tunze 6060 is too strong for a 55gallon tank? I currently have 2 koralias evo 750's and im not pleased with the quality and the upkeep. thanks