sorry if i can across as hating on aquarium pumps, I just havent seen any kind of water cooling loop in my life that looked as cruddy as that.
I understand that in their own respects that aquarium pumps have both pro's and con's.
However I am more of a follower in the commecial side of water cooling and not the diy side.
My advice, save up the money and buy a nice custom loop, you wont regret it, and the nice thing is, alot of the higher end blocks are compatible with many different sockets and you can continue using the same kit for many years. Mine has been through three different computers with 3 different sockets...
-aspire