air splitter

I have a bubble wall in my aquarium and I was wondering how to get MORE oxygen in my tank, other than live plants. Should I put in another bubbler, like an air-stone and have them run at the same time? My little cories just don't seem to be getting enough oxygen. I also keep my filter running...

Hi I’m new her and desperately seeking answers or ideas. I have an 80cm air bubble curtain and an aqua one infinity 950 air pump. Only the middle of the air curtain works. As the air pump has 2 outlets on it, I was looking at getting another air pump and wanted to know if I got a 2 splitter...