Filter sucking fish's oxygen

I don't know if it's just me but every time I turn on the filter I notice that my goldfishes would rise to the surface and what looks to be gasping for air. However, when the filter is off they're fine and swim about freely. Can the filter current be too strong? Do I have to leave the filter on ALL the time?

 

The filter really needs to be on all the time for the beneficial bacteria to survive. Most filters have a way to slow the flow down if you think it's too strong. what size is the tank? How many fish do you have in it? What size is the filter? sorry for all the questions.
Carol

 

I don't actually know what size the filter is because it came in the starter kit. I would assume that the factory would know what size filter to put in a 2.5 gallon tank. I also do not know if I can adjust it...is there a way to find out? I tried looking at the filter but there doesn't seem to be a notch or dial for adjustment. On top of that...I'm just fish-sitting...not actually my fish but just concerned about them.

 

I don't know if it's just me but every time I turn on the filter I notice that my goldfishes would rise to the surface and what looks to be gasping for air.  However, when the filter is off they're fine and swim about freely.  Can the filter current be too strong?  Do I have to leave the filter on ALL the time?
[/quote/]MOST OF THE TIME DO YOU FEED YOUR FISH WHEN YOU TURN ON YOUR FILTER, THIS HAPPENS TO ME WHEN I GO NEAR THE SIDE OF THE TANK MY GOLDFISH COMES VERY FAST AT ME THINKING I'M GOING TO FEED IT THEN STARTS TO NIBBLE AT THE WATER SURFACE.

 

Yep your right it's probably expecting to be fed.
Also as a side note a 2.5 gallon tank isn't big enough for a goldfish. Because goldfish are such heavy waste producers we usually recommend 20G for the first goldfish an 10G for each additional goldfish. You stated you were just fish sitting maybe you could recommend the fish owner get a bigger tank for his goldfish or direct them here we would love to hace them with us too
Carol

 

I told the owner to get a bigger tank. So they got a bigger tank. But I still think it's not big enough...it's a five gallon. :-\ But you can do so much right.

 

that's better than the 2.5 gallon tank but will VERY soon need to be bigger.
Carol

 

The filter needs to run at all times for water circulation also, to allow the 'bad air' to escape and oxygen to get mixed in. This goldfish may be gasping for air, because there isn't enough in his water. You could add a bubble stone, keep the filter on at all times, then if he still does it, you could be sure he was just begging.

Fish in the Frozen North 8)