I noted some possible hypothesis and observations recently when I overloaded a well running 20 Gallon tank with some 50 Cardinals, 30 shrimp, 6 Killis, 24 cories.
I added another 24 King emperor tetras.
I allowed the plants to grow up more: poor growth, poor circulation, less CO2.higher pH. Same rate of CO2.
Less O2.
I hacked the plants back: more CO2, lower pH, high O2.
Overall, better growth.
When I removed the emperors, the next day the tank pearled much more than the last 3 weeks when I added the emperor's.
The tank haqd been doing well prior to adding these fish and had a max load of the fish load minus the emperor tetras.
Adding these fish pushed the system too far and caused poor plant growth, some slight melting, slowed growth rates, lower O2.
The lowering O2 and reduced pearling may be a function of less bacteria and less fish consuming the O2.
But the plant growth appears better certainly.
Maybe the reduced NH4 production and the reduced O2 demand are playing dual roles.
In any event, NH4 and O2 play a large role here in the appearance of the tank.
And removal of the fish load really produced a dramatic result.
When plants pearl well, they also might push algae off and help drive bacteria cycling rates much faster(more O2).
So over loading a tank might be a function of reduced O2 and more NH4 that affects the plants, algae and the fish health, not just NH4 alone.
Adding NH4 with high O2 might be okay, whereas adding NH4+ low O2 might not.
Is this due to the available O2 that allows the tank to handle more NH4?
I have O2 gas, so I might add that to see.
Amano uses low fish loads, and most scapes do.
I'm interested in combining high fish and high plant loads together.
I think you have a lot more play and wiggle room with low fish loads and low NH4, adding more O2 seems to drive the bacteria. but how does it drive plant growth?
Do higher fish loads and lower O2(adding more NH4 and less O2) increase plant growth? That's what some claim(NH4 is preferred and less O2 produces less photorespiration).
But I do not see it in any tanks I've done this treatment to.
If I add some NH4 from salts, then I rarely see it, if I add a lot of NH4, then I do.
But adding less NH4, combined with less O2, this clearly affects bacteria as well, and perhaps they, rather than the plants, are controlling the NH4.
If you assume that plants like and prefer NH4, then we should see better, not worse growth(not considering algae blooms) in plants right?
I did not see that however.
Good bacteria cycling, higher O2, low to moderate fish stocking rates, then you can likely add some NH4 without too much issue, but at higher levels or with lower O2, or high fish loads............then probably not.
I'll need to think and look into it more, but it seems that there's a relationship there and adding NH4 to a low fish stocked tank with good plant growth/high O2, may not have much to do with plants as it does with the bacteria.
Whereas in an overloaded tank, the NH4 and lower O2 might drive this to a poor state.
High fish loads like this are certainly not good for plants, even with 2-3x a week water changes and nutrients, good CO2 etc. No algae formed doing this, just bad plant health, growth, less pearling, lower O2.
Regards,
tom Barr
I added another 24 King emperor tetras.
I allowed the plants to grow up more: poor growth, poor circulation, less CO2.higher pH. Same rate of CO2.
Less O2.
I hacked the plants back: more CO2, lower pH, high O2.
Overall, better growth.
When I removed the emperors, the next day the tank pearled much more than the last 3 weeks when I added the emperor's.
The tank haqd been doing well prior to adding these fish and had a max load of the fish load minus the emperor tetras.
Adding these fish pushed the system too far and caused poor plant growth, some slight melting, slowed growth rates, lower O2.
The lowering O2 and reduced pearling may be a function of less bacteria and less fish consuming the O2.
But the plant growth appears better certainly.
Maybe the reduced NH4 production and the reduced O2 demand are playing dual roles.
In any event, NH4 and O2 play a large role here in the appearance of the tank.
And removal of the fish load really produced a dramatic result.
When plants pearl well, they also might push algae off and help drive bacteria cycling rates much faster(more O2).
So over loading a tank might be a function of reduced O2 and more NH4 that affects the plants, algae and the fish health, not just NH4 alone.
Adding NH4 with high O2 might be okay, whereas adding NH4+ low O2 might not.
Is this due to the available O2 that allows the tank to handle more NH4?
I have O2 gas, so I might add that to see.
Amano uses low fish loads, and most scapes do.
I'm interested in combining high fish and high plant loads together.
I think you have a lot more play and wiggle room with low fish loads and low NH4, adding more O2 seems to drive the bacteria. but how does it drive plant growth?
Do higher fish loads and lower O2(adding more NH4 and less O2) increase plant growth? That's what some claim(NH4 is preferred and less O2 produces less photorespiration).
But I do not see it in any tanks I've done this treatment to.
If I add some NH4 from salts, then I rarely see it, if I add a lot of NH4, then I do.
But adding less NH4, combined with less O2, this clearly affects bacteria as well, and perhaps they, rather than the plants, are controlling the NH4.
If you assume that plants like and prefer NH4, then we should see better, not worse growth(not considering algae blooms) in plants right?
I did not see that however.
Good bacteria cycling, higher O2, low to moderate fish stocking rates, then you can likely add some NH4 without too much issue, but at higher levels or with lower O2, or high fish loads............then probably not.
I'll need to think and look into it more, but it seems that there's a relationship there and adding NH4 to a low fish stocked tank with good plant growth/high O2, may not have much to do with plants as it does with the bacteria.
Whereas in an overloaded tank, the NH4 and lower O2 might drive this to a poor state.
High fish loads like this are certainly not good for plants, even with 2-3x a week water changes and nutrients, good CO2 etc. No algae formed doing this, just bad plant health, growth, less pearling, lower O2.
Regards,
tom Barr
