Is airation at night needed when injection co2?

Here is a list of fish in a well planted tank and i have co2 that i want to start injecting but people say that if you got a fair few plants at night it will releases co2 when the lights are off.

1 Large altum angel/ maybe fake one but still my baby
4 clown loachs small 5-6cm long
3 Congo Tetras (Large) 8cm long
1 Pearl Gourmai 6-7 cm long
1 Pleco 9cm long
1 Pictus Catfish Huge 14cm (keeps to himself under a log)
5 Black Widows 4cm long
3 Black Neons
5 New Red Turks Discus

My question i ask is at night do i need to add a air stone i never had in the past when i was injecting co2 at night time when the lights are off ?
What do you others do at night time when the lights are off add air or just leave it be?

Thanks guys..

PS: The only reason i ask is that dicus like lots of airation and just don't want to wake up to floating discus.

Rick. :D

I have a pressurized CO2 system with a selanoid (sp?) and I don't have an airstone. The return filter splash will help in outgasing the CO2 at night when your plants also contribute to CO2 saturation. The plants don't put out enough CO2 to crash the PH when the CO2 is turned off. No air-stone needed

why would you want to inject co2 at night ????photosynthesis can only happen when light is present, plants give out co2 at night.

You should check out this thread. I think it covers all you need;)
http://www.discusforums.com/forum/viewtopic.php?t=8234