How much does a tightly fitting lid impact gas exchange?

[Schuyler]

If I'm relying on surface agitation for aeration, then how much less effective is that if there is a tight lid?

There are always gaps around wires and tubes so it's not like it's sealed.

Has anyone spent the money on dissolve has testing kits to experiment with anything like this?

[Odd Duck]

On 11/17/2022 at 4:04 PM, Pepere said:

If you have an air pump putting air through an airstone you will have great air exchange under that lid.

If a wave maker or powerhead disturbing the surface, maybe a bit less… espe ially if you also have CO2 supplementation.

Co2 is slightly heavier than atmospheric air.

 

Came here to say this but you did it even better @Pepere because I wouldn’t have thought of the CO2 since I’m all low tech.  Pumping air into the tank is the solution to, or prevention of, many problems for fish tanks.  Attach the air to a sponge filter with a battery UPS on the air pump and it’s also insurance for power outages.

[Schuyler]

On 11/18/2022 at 8:49 AM, Pepere said:

If one is supplementing with CO2 and does not wish to run an airstone in the tank as it causes co2 outgassing faster, you could just pump air under the lid to dilute the co2 concentration between lid and water.

 

all of this is theoretical as I have not done any direct measurements yet.

If an O2 meter weren't $100 I would definitely be doing some experiments

I'll probably end up throwing in an air stone to run at night when the plants aren't making O2 just to be safe