Flowrate Of Filter In goldfish Tank, what u guys think Options

[d_golem]

After reading recent shoutbox posts, I'm starting to question my belief that a goldfish tank must have at least 10x tank volume/hour filter flowrate. A prominent member of the forum suggested only 1x flowrate and claimed only uses 2 sponge filters in his 4 ft tank.

I can see the logic in having 10x flowrate as goldfish are messy fish, but after reading some posts here and seeing that most of you guys only use air pump powered sponge filters, now I have some doubts about the 10x theory. Is that amount of flowrate really required to allow efficient filtration? Or is it only good for debris/poop control? Do simple air pump powered sponge filters provide adequate surface area for bacteria to grow to handle the amount of waste that goldfish produce?

Say u got two 200-litre tank. One is using 2 canisters with total flowrate of 2000l/h. One is using two large-sized sponge filters. Which one do you prefer?

I'm really interested in what the expert bros say.

Cheers

[CyberET]

its more of increasing contact time between the bacteria, and the water. high flow rate tries to solve it by doing it many times, slow sponge filter slowly filters and makes sure everything gets done.

of course other factors like dissolved oxygen plays a part.

one main reason why a number of us uses sponge filter, is the ease of cleaning. i tried canister, and i hate the cleaning process.

the other reason is the water turbulence that high flow rate creates. delicate varients like bubble eyes may turn into burst eyes @ the water flow inlet.