Fish swimming into glass?

Hey guys! I have a 20H with 1 female honey sunset gourami and 4 male guppies. They swim into the front side of the glass and the two other sides (not the back). Or they will just stay there and swim alongside it. They do not always swim directly into it, sometimes on an angle. Tank is cycled.

Parameters
0 ammonia
0 nitrite
3 nitrate
7.9 ph
78.7 Fahrenheit

Thanks.

 

My guppies do this when they can see their reflection in the glass. They swim up and down playing with their reflection. They also swim up and down the back of my tank playing in the bubble wall.

 

I agree, this is fairly normal behavior. Fish see their reflections in the glass and are interested to see a visitor.

Sort of like "Flo" from Finding Nemo

 

Whenever my Endlers see me, they swim super hard into the top of the glass. It's their way of demanding food from me. Needy little fishies lol. I'll get a big 'ol swarm of fish swimming into the glass at me.

 

Oh okay thank you!