what would happen

my betta is in with a filter just keep it on low bcuz thats wen he'll have trouble swimming and his fins mite get sucked up in the filter tube.
 
I have a betta in my 16 gal with platys and cories. I have an Eclipse 1 hood. Since bettas don't like too much agitation I turned the filter outflow toward the back wall of the tank (as much as I could without shooting the water over the side!). He seems happy and healthy!
 
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