"Dave Millman" wrote in message
...
wrote:

I disagree - I use a block of filter foam over the intakes of my Ehiems.
Medium planted tank (90 gallon) medium population. Every water change
(weekly) clean the prefilters. easy.

Graham Broadbridge )
wrote:
Q. What does pre filtering achieve in a normal
: planted tank? A. Daily cleaning of the pre-filter :-)


I'm with Graham on this one. My cannister is up to three months between
cleanings.
Prefilters clog fast, then faster with age.



a prefilter in a "heavily" planted tank should allow you more time between
cleaning the canister. It's a lot easier to remove a block of sponge over
the intake or the commercial prefilter that will fit right onto the intake
tube and rinse it then it is to disconnect a 404 filter and remove and clean
all the media. Regardless of prefilter or not I clean my 404 about once
every 4-5 weeks. Not hard to tell when you have used a prefilter or not.

Rick