I was reading Tropical fish Hobbyist Magazine and I went directly to Takashi Amano section to look at his aquascapes. I noticed in his data of his set-ups, he adds aeration for 14 hrs after lights are out. I would like to know for any other reason besides off gassing CO2 and creating more O2?
With canister filters, the CO2 stays higher than say with a wet/dry sealed filter(another thread on how to correctly set one up for a planted tank) at night time.
Some use a powerhead or a airstone at night to help add O2 for the fish, this does not help the plants however(got nothing to do/help for them one bit).
If you use a wet/dry, then you can have a high fish load and healthy system without doing this.
ADA tanks tend to have VERY sparse fish populations, and low current.
If you have higher current, then enough O2 comes in 24/7 to avoid this altogether.
Some folks do not like higher current.
I do.
Since the O2 is also higher during the day(I've used a calibrated O2 meter to measure it over the day at 15 min intervals), I have more flexibility to add more CO2 since there's les sO2 stress to the fish.
Fish also get more exercise in higher current. A good rule is to have enough surface movement to just not quite break the surface.
If you really aerate and break the surface, you will degas the CO2 too rapidly.
A sealed(eg duct tape the top edge and air vents) wet/dry chamber(not the down stream sump) will redissolve any degassed CO2, but since O2 and CO2 are independent, it still adds more O2 as the water coming down the stand pipe still enters the chamber and the added O2 dissolves, just like the CO2 does.
Aeration at night is not needed for such systems, even with 5x more fish loading than the ADA tanks.
Also allows a lot more wiggle room dosing CO2 without stressing fish as much.
Since improper CO2 gas usage is the no1# killer of fish in planted tanks.........not a bad idea to work on.