glad i wasnt the only one jmhart.... 9 bn plecos rip..... if you have half a brain it shouldnt be a problem. might want to add more light.
Can Co2 kill fish?
- Thread starter Diann62
- Start date
Lupin
Registered Member
- Sep 21, 2006
- 21,430
- 13
- 0
- Real Name
- Paul
Have to admit I almost lost my whole stock of South American fishes a few years back when I did not notice I was using a defective gauge for my pressurized CO2. The repeated incidents eventually destroyed my BN, shrimps and rams.
I've killed fish with DIY CO2, so yes, it's perfectly possible. If CO2 goes above a certain level, it will no longer diffuse out of the fishes' gills, so it kills them not by poisoning them, or replacing the oxygen, as some have thought, but simply by making it impossible for fish to unload their CO2 from their blood to replace it with O2.
This is because CO2 is lost from the blood by simple diffusion. If there's not a high enough difference between the CO2 concentration in the blood and the CO2 concentration in the water, this won't happen (remember diffusion gradients from chemistry?). It's like expecting a truck to spontaneously roll along the flat or even uphill. Ain't gonna happen.
In low light, CO2 will do no good at all. It's not the limiting factor for photosynthesis. Only where there is plenty of light and ferts, and therefore CO2 is the limiting factor, does it actually work. It's like making bread. If you've only got so much flour, it doesn't matter how much yeast you add, you won't get any more bread.
This is because CO2 is lost from the blood by simple diffusion. If there's not a high enough difference between the CO2 concentration in the blood and the CO2 concentration in the water, this won't happen (remember diffusion gradients from chemistry?). It's like expecting a truck to spontaneously roll along the flat or even uphill. Ain't gonna happen.
In low light, CO2 will do no good at all. It's not the limiting factor for photosynthesis. Only where there is plenty of light and ferts, and therefore CO2 is the limiting factor, does it actually work. It's like making bread. If you've only got so much flour, it doesn't matter how much yeast you add, you won't get any more bread.
I have 130 watts of compact fluorescent lighting above my 55g discus tank, and they have been doing great. I have a red tiger lotus which produces a number of lilly pads on the surface of the water, as well as a few other plants which provide some shade for them, but they are never shy to come into the brightly lit side of the tank. As a matter of fact, my spawning pair preffer to spawn on the brighter side of the tank. (I know that's mostly irrelevant, just figured I'd point it out)
With a 110g tank, you're looking at needing something like 250-300+ watts if you want to get into plants which will benefit from CO2 dosing.
