Does changing canister filter impact co2?

[Mattlikesfish36]

I upgraded to the fluval 207 after using the 107 for about a year in my aquarium. I haven’t changed anything other than the canister filter itself, but my fish are showing signs of co2 overdose. My male apisto is hanging out at the top of the tank and my female is lethargic at the bottom. Would upgrading to a filter with more flow change the amount of co2 in the water? I am using an inline diffusor but I haven’t touched anything with co2 in weeks. Does the faster flow rate mean that more co2 gets into the water even though I haven’t adjusted my needle valve? I did a water change and have an air stone in the tank now 

[Remi de Groot]

The amount of co2 leaving or oxygen entering the tank could be different because of the flow change i guess.
Thats why it's almost impossible to tell someone how much co2 to add. Because every tank and every set-up is different.

The longer the co2 bubbles stay in the water before touching the surface how more co2 will be dissolved in the water.
When the bubble hits the surface and pops the left over co2 in the bubble will just go up in the air instead of the water.

Also the amount of movement of the surface affects the amount of gas excange (oxygen and co2) between the water and air.

[Mmiller2001]

Indeed it will. The higher flow alone will better CO2 distribution. Make sure to improve surface agitation. Also, adding a surface skimmer will assist in oxygenating the water.

[Mattlikesfish36]

@Remi de Groot @Mmiller2001thanks to you both for the feedback! I’ll get my surface skimmer up to full speed (currently at about half speed) and see how it goes 

[nabokovfan87]

On 12/31/2022 at 6:52 PM, Mattlikesfish36 said:

upgraded to the fluval 207 after using the 107 for about a year in my aquarium. I haven’t changed anything other than the canister filter itself, but my fish are showing signs of co2 overdose. My male apisto is hanging out at the top of the tank and my female is lethargic at the bottom. Would upgrading to a filter with more flow change the amount of co2 in the water? I am using an inline diffusor but I haven’t touched anything with co2 in weeks. Does the faster flow rate mean that more co2 gets into the water even though I haven’t adjusted my needle valve? I did a water change and have an air stone in the tank now 

Depending on the output, yeah it could make sense.

If you have something that isn't hitting the surface in the same way you don't off-gas as much.  More flow = better circulation (input and output is modified) which means that the CO2 is getting around the aquarium much easier.  Best thing to do is to knock it down a little and monitor, among other things mentioned above.  I highly recommend purchasing the x07 spraybar kit.

[Mattlikesfish36]

On 1/1/2023 at 4:25 PM, nabokovfan87 said:

Depending on the output, yeah it could make sense.

If you have something that isn't hitting the surface in the same way you don't off-gas as much.  More flow = better circulation (input and output is modified) which means that the CO2 is getting around the aquarium much easier.  Best thing to do is to knock it down a little and monitor, among other things mentioned above.  I highly recommend purchasing the x07 spraybar kit.

@nabokovfan87thanks for your reply! I have been flirting with the idea of a spray bar but I love the look of the minimalist Aquario Neo output I have on my canister. Maybe I’ll go for it someday though 

[nabokovfan87]

On 1/1/2023 at 2:23 PM, Mattlikesfish36 said:

@nabokovfan87thanks for your reply! I have been flirting with the idea of a spray bar but I love the look of the minimalist Aquario Neo output I have on my canister. Maybe I’ll go for it someday though 

it's a night and day difference on the flow, if you run CO2..... I would encourage it.  I wish I had a canister, I use the kit on a pumphead.  The aquario stuff is really cool though, I totally understand!