Fish Swimming Against Glass

Hi. I have a minnow in a 3 gallon tank. I am moving him to a 15 gallon and adding some more fish soon.
Recently, I noticed that he was swimming at the back of the tank. He also opens his mouth to breath. It almost seems as if he wants to leave the tank.
I should have the new tank cycled and ready in a month.

 

Photo, water change schedule, species of fish, water parameters, temperature? Could you please provide these things so I can help? Thanks

 

Photo, water change schedule, species of fish, water parameters, temperature? Could you please provide these things so I can help? Thanks

I do a water change every other week. I do not know the water parameters, but I believe the temperature is 78 degrees Fahrenheit. I got the minnow from my local river, which is a lot colder.

 

warm water holds less oxygen than colder water.

if you don't know the water parameters you need to buy a test kit or take a water sample to the fish store to get it tested. best to do 50% water change every week. probably has ammonia building up.

 

I agree with Skavatar

 

warm water holds less oxygen than colder water.

if you don't know the water parameters you need to buy a test kit or take a water sample to the fish store to get it tested. best to do 50% water change every week. probably has ammonia building up.

Ok thanks. Should I turn the heater off. I live in an old house with a bad heater and it gets cold at night. Should I leave the heater off during the day and on at night.

 

how cold does it get? minnows usually do fine in cooler waters.

 

how cold does it get? minnows usually do fine in cooler waters.

I would say around 60 degrees Fahrenheit.

 

it'll be fine at 60'F, many can survive long durations of colder temps during the winter

 

it'll be fine at 60'F, many can survive long durations of colder temps during the winter

Ok thanks. Should I get a heater for my 15 gallon. I would get an adjustable one just in case it got too hot. I would probably set it to 68-72 degrees.

 

if you get tropical fish, then you will need a heater.

 

if you get tropical fish, then you will need a heater.

Ok thanks