External Canister vs Internal Power filter

[Simon Bloomer]

Hi all

I realize this topic might have been flogged to death, but I am seeking
advice. I currently have a few Malawi's housed in a 243l tank with a 60l
sump and it's associated bio media. Due to space constaints I would like to
reduce this to a 184l tank (36"x18"x18") - with no sump My question is
this - which is better, external canister vs internal power filter.

I was originally considering a Fluval 204 (or possibly a 304). Eheim in
South Africa is just far too expensive. I was speaking to couple of the
local dealers, and some of them say a couple of internal power filters tend
to be better in the long run... Because a) they are quieter, b) less prone
to failure c) cheaper d) higher filtration rates for a give cost.

My feeling is to go for the canisters because a) they are easier to clean -
no hassle in digging around in the tank and b) more efficient with a larger
filter volume and space for good bio filtration, but at the price of lower
filtration rates.

Which would most people advise? Also, I like the idea of the corner surface
skimmer box which I have in my current setup. Can this be duplicated with a
canister - although I see the risk of the filter running dry if water levels
drop due to smoe problem.

Thanks in advance
Simon

[NetMax]

"Simon Bloomer" > wrote in message
...
> Hi all
>
> I realize this topic might have been flogged to death, but I am seeking
> advice. I currently have a few Malawi's housed in a 243l tank with a
60l
> sump and it's associated bio media. Due to space constaints I would
like to
> reduce this to a 184l tank (36"x18"x18") - with no sump My question is
> this - which is better, external canister vs internal power filter.
>
> I was originally considering a Fluval 204 (or possibly a 304). Eheim
in
> South Africa is just far too expensive. I was speaking to couple of
the
> local dealers, and some of them say a couple of internal power filters
tend
> to be better in the long run... Because a) they are quieter, b) less
prone
> to failure c) cheaper d) higher filtration rates for a give cost.

In my limited experience:
a) Internal canisters are silent, external canisters are quiet.
b) Internal canisters are more prone to failure, usually related to being
serviced less frequently.
c) Much cheaper, and you get what you pay for ;~)
d) Questionable. Divide the filter media surface area by the purchase
cost.

> My feeling is to go for the canisters because a) they are easier to
clean -
> no hassle in digging around in the tank and b) more efficient with a
larger
> filter volume and space for good bio filtration, but at the price of
lower
> filtration rates.

a) yes, and consequently they will get cleaned more often, giving better
filtration and less problems.
b) agreed
c) they also do not 'steal' valuable space from the interior of yur tank.

> Which would most people advise? Also, I like the idea of the corner
surface
> skimmer box which I have in my current setup. Can this be duplicated
with a
> canister - although I see the risk of the filter running dry if water
levels
> drop due to smoe problem.

IMO, the advantages of running a freshwater skimmer are usually
overwhelmed by the hassle of making them work.

ps: Fluval 204 (40g) and 304 (70g). For your tank (50g) and considering
you have Malawians, the 304 would be the better choice.

NetMax

> Thanks in advance
> Simon
>
>

[SG]

In article >, Simon Bloomer wrote:
> - which is better, external canister vs internal power filter.

For all the reasons NetMax listed canister is better. The 304 fluval
is probably your best choice.


>b) more efficient with a larger
>filter volume and space for good bio filtration, but at the price of lower
>filtration rates.

I would not worry about the flow rate. As you said the canister is more efficient.


> Also, I like the idea of the corner surface
>skimmer box which I have in my current setup. Can this be duplicated with a
>canister - although I see the risk of the filter running dry if water levels
>drop due to smoe problem.

This would not work with a canister, unless you had a sump. Canister
are designed to run in a closed loop pulling water from one water
level and pushing water back to the same water level. The water level
in the corner overflow will always be lower then the level in the main
tank. This will reduce the flow through the canister.

The second problem is that the overflow will run dry simply due to
evaportion. Any water that evaporates is going to directly effect the
level in the overflow. A conservative 2% a week is 3.6l. Unless your
overflow is quite large the level in the overflow will drop
significantly.