Plants and oxygenation

So oxygenation (like airstones and such) is bad for the plants because it takes the CO2 away. In theory, if you have enough plants, then you don't need additional oxygenation.

Buuuut, I thought plants expelled CO2 at night. So I was thinking: would it be an idea to put my air pump on timer, so that it's only active at night?

 

What plants are you running? Unless you are injecting CO2 it won't make a difference one way or another. The CO2 in the air and CO2 in the water will balance out, unless you are adding more CO2. All the bubbles are doing is increasing the surface area that the gas exchange can take place. If you are injecting CO2, then yes, the increased surface area will cause you to lose more CO2 out of the water.

 

Yeah, I agree with Chief I mean, if you like to have your airpump on at night, it won't hurt the plants With CO2 injections, it's a whole different story though.

 

So, does having the air off during the day possibly help the plants? Sorry to ask, it just seemed like a cloudy answer.

 

Yes air in the tank in the day is not good for them, it ripples the surface and causes the c02 to expel the water before the plants can make use of it. I only run my c02 during light periods, well actually it comes on about 30 min before lights go on and it goes off pretty much in time with lights off.

And at night plants do switch from giving off oxygen and swtich to giving off c02 and do most of there growing at this key time. If your c02 does not run through the night there is still no need to put in air bubbles, where that can help is with DIY systems where they run 24/7 on my DIY tanks, I still don't use air, I just turn up my filters output levels so they churn up the surface a bit to burn off the c02 in the water that is not needed or getting to strong.

Or in tanks that you worry about ph shifts if your c02 is off to long ie very soft water, then you have to find the balance. Some people inject c02 pressurized 24/7 and then at night run air to burn off excess or lift there spraybars to the surface or up there outflow on their HOB filters to hold a steady c02 level which in turn keeps ph from swinging. Basically test your c02 right before lights on and right before lights out and see if you have a swing and you make adjustments based of the level of the swing.

 

OK, thanks MrWaxhead and Isabella.

No, not using CO2.

Basically, I like the idea of running oxygen pumps for the fish. It just feels more wholesome. I don't like the idea of a bubble-less tank at night in a planted tank. Feels like the fish may become oxygen-starved or something.

But I don't like the idea that it's not good for the plants if run during the day. So I was thinking maybe the fish can still have their bubbles, only at night.

I don't think the bubbles at night will be good for the plants or anything, but just wondering if it would be bad for them? If not, then maybe I'd like to do that.