May be just to find out how good/bad the fluval's are from his actual experience in order to make the comment that he did...? Just a complete guess!
I personally take opinions from those who have both fluval's and eheim's more seriously than from those who just have only one type for more (hopefully) unbiased comparisons.
One thing i can say is dont use the blue filter pads they recommend since they get to much debris and cause alot of micro bubbles.
Only down fall is that eventually the lid with the gasket around it doesnt complete the job. Vasoline around the lid will seal it. Otherwise no complaints about this filter at all i bought one and the tank remains clean and nice.
Bought one for a 210gallon ran it for a month or so with the trays with scrubbies in the top tray then bio in the last two. found a member on here that has done mods to the fx5 his name is jgrays152 http://www.monsterfishkeepers.com/forums/showthread.php?146707-Fluval-Fx5-Modification.&highlight=
Did a few of his mods my canister now hold way more media then 6 liters.
Other than that the canister is a bit heavy.
I never said that I bought it. Because I didn't. But I am saying that I still do not expect to get 15 years trouble free service from it. Now does that make it a bad buy? No.! You should get many good years of service from it. I did get a Fluval 405 brand new in the box in november of 2009. I did not spend a penny for it. The other day I come home and find my 180 gallon tank only has about 30 gallons of water left in it. The source of the problem was that 405. It cracked at the base of motor where the handles keep it closed. Which is a known problem for them. I called Hagen and should be getting a new one once I send this one back.
I got a couple of Fx5s on my 120g. One is filled with all Bio-Max and the other is filled with Ammonia Remover, Carbon, and Filter Pads. The filter pad is started to clog easily, so those will need replacing, but other than that, they run great.
I have a fx-5 for over 5 years and i swear by it. I have 2 on 2 different tanks and has always done good for me. easy to clean and easy to set up, it is very powerful.
