Is there anything wrong in adjusting the flow to the maximum rate that the
filter can handle even if it exceeds the recommendation?

In other words, is too much filtration a bad thing?

The key is "...the filter can handle...". Providing that the filter really
handles it, it doesn't make much difference, but figuring out exactly what
the filter can handle is tricky. Too much flow encourages channeling -
where the water manages to bypass most of the filter medium. Too little
flow can mean that the filter actually isn't working up to its capacity.
So, as fast as it can handle without channeling is good, but identifying
channeling is difficult. Derek

One of the ways one can identify channeling is murkiness in the water that
wasn't there prior to turning the flow up. Water quality, by testing the
water may be another.

In my system (at the Demon. Pond) channeling in the pre-filter causes the
bio-filter pads to clog faster. We fixed that this year by cleaning the
pre-filter every 4 weeks no matter what, and it helped that we secured the
bio-pads with hardware cloth (wire mesh) so they couldn't collapse when
they got muck on them. The bio-filter is horizontal flow so we could spray
the muck off the front pad as long as it didn't collapse. Turned out, only
the first pre-filter cleaning, which had to go longer than the 4 weeks, we
did have to spray that front pad off. After that, it wasn't a problem.

At home, I don't have this problem at all, I only clean the prefilter 4
times/year and it runs 24/7 all year long. Fish load is surely similar, the
D.pond has more fish, but they're tiny in comparison to what I have at
home. Pound for pound I may actually have more fish.

Long story, short answer, I don't think there has ever been a case of too
much filtration, but blowing by the filter, as Derek mentioned via
channeling, doesn't count. ;-) ~ jan

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See my ponds and filter design and the Demon Pond:
www.jjspond.us

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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