Sump filter/aeration

[Joey_Jojo]

I have always had the general idea that, given the fact that the water is cascading over a compartment of bio balls, my sump filter is aerating my water and I probably don't need an air stone. Do you folks think that's accurate?

[RockMongler]

The biggest issue I see with that assumption is that a lot of the oxygen picked up by the cascading water could get sucked up by the bacteria that are living there, but that is assuming the worst possible case.  Someone else might see other issues.

If I had a sump, I'd probably still get an airstone in that area just because it has zero downside besides possibly sound/electric usage.  But, I'm the person with a 20 wide with a hang on back, and a stream flow manifold and an airstone.  I go with overdoing it because I don't want to risk not doing enough.

[Andy's Fish Den]

To an extent it would be if you are using what was known in the past as a trickle filter where the water goes into a tray with a bunch of holes drilled in it, then trickles down through some bioballs. A lot of people tend to shy away from those filters anymore, and instead use a bunch of sponges and filter mats for biological filtration. If you do want to make sure that you have plenty of aeration but don't want an airstone in your display tank, you could always set an airstone in the sump someplace and it will aerate the water in there which then is pumped into the display. 

[Joey_Jojo]

5 minutes ago, Andy's Fish Den said:

To an extent it would be if you are using what was known in the past as a trickle filter where the water goes into a tray with a bunch of holes drilled in it, then trickles down through some bioballs. 

I does indeed pass through a tray like you describe. And in fact the bio balls compartment is not submerged, so it is trickling through emerged bio balls before submerging again.

[lefty o]

aeration is about surface area. just about any way you could possibly configure a sump, will add tons of surface area for water to be able to oxygenate. you could always add air stones etc, but you more than likely have water that carries plenty of oxygen.

[Andy's Fish Den]

1 hour ago, Joey_Jojo said:

I does indeed pass through a tray like you describe. And in fact the bio balls compartment is not submerged, so it is trickling through emerged bio balls before submerging again.

That's how the sump trickle filters were made years ago, my first sump filter I had on a tank in the early 90s was like that. I am sure with plenty of surface area of water being exposed to air as it trickles through the bioballs that more oxygen is being added to the water. 

[tolstoy21]

Just use return pump outlets to create surface agitation.

In my setup, between the water gurgling in the overflow, water flowing through the sump compartments and going over a 'bubble trap' kind of gentle water fall, and then return pumps agitating the water surface, I feel like i have plenty of aeration. 

All of this depends on system design, but I'm guessing your putting water back into the tank somehow and that's an opportunity to agitate the water surface for gas exchange, if you feel like you need more aeration. 

Edited April 14, 2021 by tolstoy21