Tank turnover and Oxygen content for Zebra Plecs

[gtp]

Ok I have a tank around 100 litres which is going to be exclusively used for a few Zebra's.

I have two Fluval 3 internal filters which each give a 700 litre per hour turnover, and I have an Aquaclear 20 Powerhead (just used for waterflow, no air) which gives about 500 litres per hour and an Aquaclear 30 Powerhead which gives about 550-600 litre per hour (with air being pumped into the tank).

Adding this up equals roughly 2400 litres per hour tank turnover. Thats 24x. Is that too much? The way I have postioned the filters and pumps ensures that there are very few 'dead spots' in the tank where food may settle.

Second question is... at night, can the Aquaclear 30 Powerhead be turned off? Its the one that pumps the air into the tank, but it makes a hell of a noise and its in my bedroom. In Rio Xingu, would oxygen content lower at night at all? The tank flow will still be 1900 liters an hour with the rest of the stuff, but this is the only powerhead which is giving off loads of bubbles.

Thanks

[eeeeemo]

Welcome to AQ QTP!
i am jia yuan, hope the stuff below helps, its from my experience.

turnover rate does not matter as much as quality of water.
you can have plenty of pumps that filter the water 264796729647291674x but if you do not get good media that cultivate plenty of beneficial bacteria that "cleanses" the water, the water will not be clean enough to induce breeding.
my zebras actually hate the noise produced by powerheads that are too strong.
it will be good to have powerheads that spray bubbles and that one should do enough to oxygenate the water, i believe the high flow rate is mostly for oxygenating the water, not really that they appreciate it. they do like a bit of a flow though, not so strong that it pushes their tails as they hang around.
food has to fall on the ground for them to eat it, leave some dead spots for them, easier to siphon the dirt anyway. just unsightly but you won't see it much as the lights are supposed to be dimmed.

[gtp]

So providing there is enough oxygen being pumped into the tank, water flow isn't of huge importance?

The water flow currently in the tank is very high, as I say it is around 24x turnover. Should I take the one powerhead (the ones thats not blowing bubbles into the tank) out to reduce the flow to around 19x turnover?

Also, is it possible to turn the powerhead blowing bubbles into the tank off at night? Will the decreased oxygen stress the fish? There would be less water flow, and alot less oxygen, would anything similar happen in the wild?

[eeeeemo]

hmm i just realised this thread is sort of in the wrong subforum.
to answer your qn. it is really up to personal preference. after awhile the fishes will get used to it and adapt.

however, you should not stop the bubbles at night. oxygenation should be of next importance after water quality for zebras.

my advice is get a canister and then top it up with a spray head from eheim. extremely quiet and you get clean water too!

[gtp]

After getting a venturi valve for the aquaclear powerhead there has been a fair noise reduction. I've left the main powerhead on permanently now and only turn it off for an hour at feeding time.

The other powerhead I turn on for an hour in the morning and an hour in the afternoon sometimes to kick up any left over food from the night and get it into the filters.