Oxygen & Co2 confusions

[leap]

I can't wrap my head around it.😕

My tanks are heavily planted, I have Eheim canisters with spraybars above the waterline, plus internal aeration via aquael sponge filters with venturi's, placed low down in the tanks.

If I angle the spraybars towards the back of the tank the bettas cope - but I'm not sure it does much for water circulation?

Adding the internal sponge filters seems to be the only way(?) to get a bit more circulation going in my betta tanks (no mean feat!) without distressing/damaging the fish. I use excel.

Some stress the importance of oxygen in the tank, others say it drives off Co2.

Am I just driving off the excel?

 

[ian_m]

Excel is gluteraldehyde (or similar) and is not driven off by excess agitation, you are confusing gaseous CO2 which is outgassed by agitation.

Some fish and/or plants are sensitive to Excel/gluteraldehyde.

O2 is nothing to do with it. As you have water movement, probably excessive in your case, the water will be at equilibrium with O2 in the air. Further agitation won't add any more.

I suspect your issue is having the spray bar above the water line is causing too much noise and disturbance, which explains when you point the spray bar to the back of the tank they are not distressed.

Trying running with the spray bar below the surface of the water. There will be enough O2 exchange on the water surface so lack of O2 won't be an issue.

 

[leap]

Ahhh, thanks for clarifying this and for your help.🙂