Dangers of CO2? Can it kill my fish?

[Joegourami]

Hello.

I've been thinking and I want to add extra CO2 to my 40 gallon to boost the growth of my plants, the light is a 30 watt T8 full spectrum and silica sand substrate with root tabs near the plants. But is there any danger in over dosing it besides pH drop? I add a photo so you can help me better.

 

[aqua_chem]

CO2 can essentially suffocate fish at high enough levels. However, the only cases where that should happen is in instances of gross user error, negligence, catastrophic hardware error, or some combination thereof.

If people compared the number of fish that have been killed with CO2 OD and the number that have been killed by fish food OD, I think you would find that fish food would be a leading cause of untimely fish death.

I will say though that I've ran levels of CO2 higher than anyone with fish in a tank has any business doing, and I haven't lost any fish to it yet.

 

[Joegourami]

CO2 can essentially suffocate fish at high enough levels. However, the only cases where that should happen is in instances of gross user error, negligence, catastrophic hardware error, or some combination thereof.

If people compared the number of fish that have been killed with CO2 OD and the number that have been killed by fish food OD, I think you would find that fish food would be a leading cause of untimely fish death.

I will say though that I've ran levels of CO2 higher than anyone with fish in a tank has any business doing, and I haven't lost any fish to it yet.

Thank you, I will be careful, test frecuently pH and kH to know the concentration of CO2.

 

[aqua_chem]

Buy a drop checker so you can quickly visually confirm your CO2, and directly measure it rather than measure pH. That giant hunk of DW in your tank is going to throw off the KH/pH/CO2 charts something fierce.