First I have a 55 gallon tank with freshwater fish. I wanted to know how many hours a day or all day long should I leave my bubble wand going?

Hello growing...

You don't need the bubblewand. If you have a power filter with a gallon per hour (gph) rating of roughly 6 times the volume of your tank, then it will provide enough water movement to keep oxygen in the tank water.

It's not wrong to use a wand and if you like the bubble effect, then that's all fine. But, it doesn't do a very efficient job of getting oxygen into the tank and allowing carbon dioxide to escape. If you like it, then put it on a timer with your tank lights and run it when the lights are on.

B

__________________
Low Tech Water Building Keeper