Recommended sizes of power filters.

[Eric]

I stopped by the local Petco tonight. They're expanding their aquatics
department and had display samples of many types of power filters with charts
of the stats and manufacturers recommendations for each type of filter. I
took some notes as this issue came up a couple of days ago.

Here's the data:

Manufacturer gallons per hour tank size (gallons)

Penguin
100 20
150 30
200 50
350 75

Whisper
90 10
105 20
145 30
210 40
330 60

Cascade
80 10
100 20
150 30
200 50
300 100

AquaClear
100 20
150 30
200 50
300 70
500 110


So, with the exception of the filters for ten gallon tanks, the general idea
is that turning over the tank volume 4 or 5 times an hour is the usual
recommendation.

This sounds about right to me. Would biological filtration be that much
better with a higher turnover? I suspect not. A higher turnover might make a
difference to mechanical filtration, but I doubt anyone has that much gunk to
filter out.

Conclusion: Anyone who recommends larger powerfilters than what the
manufacturer recommends is needlessly upselling. So in this case, the filter
makers are the good guys. Of course, they do have their little scam going.
They suggest changing out media every month. I know that water quality drops
with new media, even though there's fresh carbon. That's how they get you.
Kinda like inkjet printers.

-E

[NetMax]

"Eric" > wrote in message
. sbcglobal.net...
>
>
> I stopped by the local Petco tonight. They're expanding their aquatics
> department and had display samples of many types of power filters with
> charts
> of the stats and manufacturers recommendations for each type of filter. I
> took some notes as this issue came up a couple of days ago.
>
> Here's the data:
>
> Manufacturer gallons per hour tank size (gallons)
>
> Penguin
> 100 20
> 150 30
> 200 50
> 350 75
>
> Whisper
> 90 10
> 105 20
> 145 30
> 210 40
> 330 60
>
> Cascade
> 80 10
> 100 20
> 150 30
> 200 50
> 300 100
>
> AquaClear
> 100 20
> 150 30
> 200 50
> 300 70
> 500 110
>
>
> So, with the exception of the filters for ten gallon tanks, the general
> idea
> is that turning over the tank volume 4 or 5 times an hour is the usual
> recommendation.
>
> This sounds about right to me. Would biological filtration be that much
> better with a higher turnover? I suspect not. A higher turnover might make
> a
> difference to mechanical filtration, but I doubt anyone has that much gunk
> to
> filter out.
>
> Conclusion: Anyone who recommends larger powerfilters than what the
> manufacturer recommends is needlessly upselling. So in this case, the
> filter
> makers are the good guys. Of course, they do have their little scam going.
> They suggest changing out media every month. I know that water quality
> drops
> with new media, even though there's fresh carbon. That's how they get you.
> Kinda like inkjet printers.
>
> -E


My understanding is that biological filtration works better at the slower
rates of water flow. Note that water flow is not directly 'changes of tank
water' due to the different filter media area surface. Canister flow rates
are typically slower than powerfilters *and* they have more filter media, so
the biological activity is much much better. When comparing flow rates,
compare powerfilters against powerfilters or canisters against canisters.

The real use of tank-changes (the typical x4 to x5 rates you saw) are to
keep a uniform temperature and to aid in the mechanical pickup of detritus.

Generally, between filtering correctly and over-filtering, you should
over-filter, for no other reason than fish grow, eat more and multiply.
--
www.NetMax.tk

[Dan White]

Eric wrote:
> I stopped by the local Petco tonight. They're expanding their aquatics
> department and had display samples of many types of power filters
> with charts of the stats and manufacturers recommendations for each
> type of filter. I took some notes as this issue came up a couple of
> days ago.
>

Thanks Eric, that was helpful.

dwhite

[Eric]

On Sun, 11 Sep 2005 08:13:35 -0500, NetMax wrote
(in article >):

> "Eric" > wrote in message
> . sbcglobal.net...

[My data on filter flow rates deleted]

>
> My understanding is that biological filtration works better at the slower
> rates of water flow. Note that water flow is not directly 'changes of tank
> water' due to the different filter media area surface. Canister flow rates
> are typically slower than powerfilters *and* they have more filter media, so
> the biological activity is much much better. When comparing flow rates,
> compare powerfilters against powerfilters or canisters against canisters.

I agree about not being able to compare powerfilters and canisters solely by
flow rate. That's why in the interests of saving time I just decided to leave
canisters out. I also agree that the quantity and type of filter media makes
a big difference. The Penguins and Aquaclears have a lot more going on with
them than the Cascades and Whispers media-wise.


> The real use of tank-changes (the typical x4 to x5 rates you saw) are to
> keep a uniform temperature and to aid in the mechanical pickup of detritus.

And I don't see how going for more than 5 tank changes per hour would aid in
mechanical pickup unless the tank is packed full of poop-machines like large
goldfish.

> Generally, between filtering correctly and over-filtering, you should
> over-filter, for no other reason than fish grow, eat more and multiply.

I agree, though I go more for combining different types of filters than using
one big filter.

-E

[NetMax]

"Eric" > wrote in message
. sbcglobal.net...
> On Sun, 11 Sep 2005 08:13:35 -0500, NetMax wrote
> (in article >):
>
>> "Eric" > wrote in message
>> . sbcglobal.net...
>
> [My data on filter flow rates deleted]
>
>>
>> My understanding is that biological filtration works better at the slower
>> rates of water flow. Note that water flow is not directly 'changes of
>> tank
>> water' due to the different filter media area surface. Canister flow
>> rates
>> are typically slower than powerfilters *and* they have more filter media,
>> so
>> the biological activity is much much better. When comparing flow rates,
>> compare powerfilters against powerfilters or canisters against canisters.
>
> I agree about not being able to compare powerfilters and canisters solely
> by
> flow rate. That's why in the interests of saving time I just decided to
> leave
> canisters out. I also agree that the quantity and type of filter media
> makes
> a big difference. The Penguins and Aquaclears have a lot more going on
> with
> them than the Cascades and Whispers media-wise.
>
>
>> The real use of tank-changes (the typical x4 to x5 rates you saw) are to
>> keep a uniform temperature and to aid in the mechanical pickup of
>> detritus.
>
> And I don't see how going for more than 5 tank changes per hour would aid
> in
> mechanical pickup unless the tank is packed full of poop-machines like
> large
> goldfish.

Applications where there are a lot of rockwork, like mbuna tanks benefit
from higher flowrates to get between the stones. This is also where
canisters are better as you can better direct the flow, though powerfilters
generally have higher flow rates than canisters.

>> Generally, between filtering correctly and over-filtering, you should
>> over-filter, for no other reason than fish grow, eat more and multiply.
>
> I agree, though I go more for combining different types of filters than
> using
> one big filter.

:o) Absolutely !!
--
www.NetMax.tk

>
> -E