Swimming at top

[Metatron]

I recently bought 4 Golden White Clouds, I also switched to an underwater filter. Now my White Clouds and longfin Zebra Danios are swimming at the surface of the water...the Danios were fine before now they seem to either be schooling with the white Clouds or they are all having the same issue....could the water flow from the underwater spray bar be too strong? I also have a bubble stone in the corner. Does not having falling water from the hob filter cause there to be less oxygen in the water?
It is a 54 gallon corner tank, getting started so pretty understocked and like I said, these are the only two recent changes...thanks for any help.

 

[toolman]

My danio's swim at the top always, and I have 2hob filter's. Anything you change in your tank will change the environment and behavior of inhabitants.

I think they're fine, just changed their behavior because you made changes. Watch them for awhile, but I believe your good.

I would suggest you research their temperature requirements though, believe danio's like warmer water than white clouds (you may have done this already). This could affect fishes behavior also.

 

[Potluck]

Did you keep the other filter running? If not you removed most of your beneficial bacteria, also under gravel filters are absolutely horrible hense why no one uses them anymore or what do you mean by "underwater" you can't just take a filter off the tank and replace it with a bran new one unless you take the media/floss whatever is in the other filter that's grown beneficial bacteria and put it in the new one. What are the water parameters?

Ammonia
Nitrite
Nitrate
Ph
Water temp

 

[Metatron]

I used the old filter media...it's not an undergravel..it's an underwater, Ovation 1000 submersible...they have a spray bar and it did seem the current was to strong...I did add an extension to the spray bar which lessened the current and that seemed to do the trick...thanks for the help [emoji106][emoji4]

 

[toolman]

Good I'm glad you figured it out.
Sometimes hard to get the idea what's really going on, the OP always has the best picture of what's happening.

 

[Metatron]

It did take them a day or so to figure it out LOL...one brave Danio seemed to lead the trend. They still hang out at the top, and together, but not literally the top of the water..now it's the top area which is nice

 

[Potluck]

My rainbows love my current they want me but my ornate tetras wouldn't handle it, it could just be a coincidence that that's what it was but non the less glad you got it figured out