whats a filter got to do with oxygen?

[Cian McLiam]

As Platypus said, the oxygen is needed by the fish, plants and the bacteria in your filter, stones decorations etc. Fish and anything else that lives under water needs to take their oxygen (or most of it in the case of anabantoids and some catfish. Whales other mammals excepted!) from the water they live in.
The oxygen in the air replaces the oxygen thats used up in the water giving back the O in H2O. The bubbles break the water surface, speeding up the release of carbon dioxide and other harmful gases, and the absorption of replacement oxygen.
This is why, when you buy fish from a petshop and they put it in a tiny bit of water and leave the rest of the bag empty. Its for a good reason, the air in the bag replenishes oxygen used by the fish in the water. If you need to travel a long distance, pure oxygen is better. All the fish need is enough water to keep the gills wet but now Ive gone way off topic, time to lay off the coffee!!

Ken

 

[aquamanis]

Hi Akhtar, air bubbles are purely cosmetic apart from the surface agitation they create. Surface agitation helps carbon dioxide and oxygen to exchange at the waters surface. Pumping air into the water dosen,t actually oxygenate the water. The only way to saturate the water with oxygen is with plants. Plants that are growing well will give off oxygen when photosenthysis occurs. With reguards to the filter, if you want more bubbles there should be a little inlet hole where the outlet of the powerhead is. This is the venturi, where you can add air to the water. Just put a piece of air tubing on the little inlet (venturi) and have the other end sticking out of your tank higher than the powerhead. As water is pumped through it sucks air with it creating millions of bubbles. You can put a small air valve on the end of the tube to restrict the amount of bubbles if needed. Platypus, not all tropical fish need to breathe through thier gills. Gouramis can breathe air at the waters surface. They have little organs (which I forget the name of that are much like our lungs). Corydoras go to the surface to force air into thier stomachs where it gets dissolved. Thats why some fish can handle higher levels of nitrites than others.

 

[akhtar]

lol

ok
thanks, and sorry latral line! i was wrong )

 

[platypus]

Gouramis can breathe air at the waters surface. They have little organs (which I forget the name of that are much like our lungs).

Yep my dwarf gouramis do this, it's so cool to watch. Apparently though they don't need to do this as their gills function perfectly well, it's just a throwback to a period in their evolution when they needed to breath air that's remained as an instinctive reaction. Not sure if this is true actually , I read it somewhere, wish I could remember where!

EDIT OK looks like I was getting my wires crossed. Here it explains it properly - I think that I read somewhere that if you see gouramis breathing from the surface, it doesn't mean you need to panic about your water having low oxygen levels, because they do it anyway through instinct. Sorry!