Oxygen in rivertank without venturi of airpump?

[Francois van Brederode]

Is it possible to increase the O2 levels in my rivertank by watermovement alone?

It is a 60ltr. tank and it now has a combined watermovement of 1400ltr/h.
That's a turnover rate of about 23x/hr.

However it is NOT equipped with an airpump or venturi.
It is in my bedroom, so the extra noise would not be appreciated by me or my girlfriend.

Would this produce enough O2 for hillsteam loaches? (sewellia/pseudogastro's)

Would adding an extra powerhead of 900ltr/h (or 1400ltr/h) increase the O2 even more, or at all?

Thanks.

[bigpow]

it's less effective than using airpump, but powerhead venturi without airpump will also work (that's what I have).
Just make sure that you secure the airline hose on top of the tank at anytime, or put a check valve to prevent backflow when pump is off.

I also stuffed the airline hose end with some foam to silent the noise.

[Keith Wolcott]

I have been curious about the same issue. I recently obtained an O2 test kit and I find that my tanks are at the saturation level. That is, the O2 cannot be increased any further. I have a large amount of water turnover (more than 40 times per hour on the 300 gallon tank), but no air stone and just a bit of rippling on the surface. I was concerned that I should increase the O2 and it would be a big benefit, but it seems that no increase is possible. Therefore, my guess is that with your very good turnover, if you have just a little bit of rippling of the water surface at one end of the tank, that you are in great shape and probably cannot increase the O2.

[Francois van Brederode]

Thanks all.

I'll still put in the extra powerhead for added current.
The O2 will probably be fine.
The fish are breathing at the same pace as the fish in a proper rivertank with all sorts of venturi and airpumps.

Just thought i'd check

[Diana]

Air bubblers and venturi systems do not add oxygen. The bubble rise to the surface, and pop. The air in those bubbles does not dissolve in the water. (If you want to nit pick then yes, the bubbles do dissolve in water. But it would take a column of water over 10' deep to dissolve those bubbles. A 2' deep tank is nowhere near deep enough to get any major amount of air into the tank this way)

These methods help a little bit by increasing the movement of water at the surface. There are quieter ways to do this, such as power heads.
A gentle ripple at the surface, and turning over all the water in the tank in excess of 10 times per hour will do a lot more for your fish than noisy bubblers.

[Francois van Brederode]

And it helps you sleep at night

I now have a turnover rate of 38x an hour with nice solid waves going across the surface.
And no noise

[bigpow]

achieving such ridiculous ratio of water turnover is a lot easier on smaller tanks.

it's impossible to do in bigger tanks. just imagine, 240g with 30x turnover rate = 7200GPH? that's just too funny.

[Diana]

I would approach that project with a very large pump in a sump, and adding some of the larger Koralias to direct some water into any dead spots.

[Keith Wolcott]

bigpow- Not so. My tank is 300 gallons and I just have 4 Tunze pumps that each move 3500 gallons/hr plus two canister filters that move 350 gallons/hr each. That's 49 times turnover per hour. I think that the loaches really like it.

[bigpow]

Keith, that's why you're the Keith-ster
I'm at least 10yrs behind you, pal.

The cost of 2 Eheim 2080 Thermo and 4 Tunze is a bit hard for me to swallow. I love my clowns, but they'll have to share with my other hobbies.

My small 55G, on the other hand, is super easy to over-filter/flow without even trying.

[wasserscheu]

my tanks are planted and the plants cover the watersurface, so my watermovement happens mostly in the ground area. My oxygen mainly is produced by plants (lights with timer which switch off during mid day but allow 2 x 5-6 hours of light periodes. That needs a bit more water reserve, to store enough O2 over night. Some plants need a bit care, some grow easier. For a hilly, plants may work, that are arranged in way so they don't disturb the water flow too much or cover only some part of the surface. Emma had a nice pic of planted hillstream tank a while ago uploaded here.