Which Are Best Internal

[007_gaz]

hi. i been checking out some the biggest internal filters like fluval u4 and interpet pf3. care to share if these on their own could handle a 4 foot tank? at the moment i have x2 internal filters and one at each end of tank, it seems a good thing to do. im douting that u4 alone could filter large aquariums, care to share views at here on the bigger internals that claim to do 200litres plus.

 

[xamy_valox]

I have a Fluval U4 and love it, it has really turned my tank around. My water levels are perfect and there is not hardly any poop lying about on the sand.
I have a 125 litre tank however, so I'm not sure how it would hold up in a much bigger tank!