I too had a problem with the propeller on mi penguin 200, the flow was too low and it would make noises too loud to allow me to sleep. So i decided to order a rena xp1 canister for mi 26 gallon. it should be here by friday, so i'll tell you how it works.
You can always buy clear hoses. As for the Marineland, I'd buy one rated for a tank slightly larger than the one you have. In other words, you have a 55, so I'd probably get one rated for a 75. The ratings on the box are best-case scenarios, and the "real" flow is usually less. Plus you'll have the benefit of extra filtering power, which is almost always a good thing. :idea: