CO2 vs fish
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They don't produce that much co2. so the difference is a lot, how much? im not sure, but lets use this as a reference. A human exhales only 4% CO2. For a human to promote growth in a plant on a kitchen table either 1) the person has to breathe a lot (until they most likely pass out), or 2) you need like 45 humans sitting there breathing on a plant.
I think by the time you get enough fish in there to provide a lot of co2 you will have major water quality issues and overstocking problems.
cheaper and easier method would be to add co2
I think by the time you get enough fish in there to provide a lot of co2 you will have major water quality issues and overstocking problems.
cheaper and easier method would be to add co2
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I suppose while we're listing differences, it's worth mentioning that even if you stocked fish in a tank to sufficiently to supply the plants with CO2, you would have to deal with day/night fluctuations as the plants' uptake changes. Injected CO2 can be controlled, but you're a better trainer than me if you can convince the fish to hold their breath at night.
Water has 6-7ppm of O2(at say 25C under optimal conditions), if you remove all this O2 and respire it as CO2, the max concentration possible would be around 6-7ppm or so at best of CO2.
So even if the fish used it all and expired it all, there's a problem when the O2 is 0ppm.
You cannot keep fish after the O2 drops to say 2-4ppm.
We can add CO2 gas however and not affect the O2 levels at all(they are independent). So we can add say 30ppm of CO2 and still have 7ppm of O2.
Respiration is a two way street, both O2: CO2 are involved at a ratio across the fishs' gills. More O2, the more CO2 can be added without ill effects, the less O2, the less CO2 can be added with no ill effects.
So good current and plant growth will optimize O2 production/addition and dosing CO2 gas will optimize CO2 so the plants can produce more O2.
We only add CO2 during the day, this is the only time it is needed for the plants, at night,m we stop and the CO2:O2 ratio goes back up and it is easier for the fish to respire.
During the day(say 8-10 hours), the plants also produce O2, so 7-10ppm of O2 is common. And the CO2 is enriched during this same time, so this balances out for the fish.
Poor use of CO2 leads to death and gassing their fish, be slow and observant with CO2, no need to rush with its use.
Regards,
Tom Barr
So even if the fish used it all and expired it all, there's a problem when the O2 is 0ppm.
You cannot keep fish after the O2 drops to say 2-4ppm.
We can add CO2 gas however and not affect the O2 levels at all(they are independent). So we can add say 30ppm of CO2 and still have 7ppm of O2.
Respiration is a two way street, both O2: CO2 are involved at a ratio across the fishs' gills. More O2, the more CO2 can be added without ill effects, the less O2, the less CO2 can be added with no ill effects.
So good current and plant growth will optimize O2 production/addition and dosing CO2 gas will optimize CO2 so the plants can produce more O2.
We only add CO2 during the day, this is the only time it is needed for the plants, at night,m we stop and the CO2:O2 ratio goes back up and it is easier for the fish to respire.
During the day(say 8-10 hours), the plants also produce O2, so 7-10ppm of O2 is common. And the CO2 is enriched during this same time, so this balances out for the fish.
Poor use of CO2 leads to death and gassing their fish, be slow and observant with CO2, no need to rush with its use.
Regards,
Tom Barr
an air stone works better than extra fish... trust me on that one.
This is true.
As well as better for the fish that are there to begin with.
Regards,
Tom Barr