I think my Betta is sick

[DragonBettaGirl]

So this is my first time on this site and I read everything I could about sick bettas while I was at work. But I don't what my fish might be sick of. I just looked at him. I have a 3 gallon 360 tank. The pump/filter runs down the center of the tank is closed and Dragon (betta) just sits on top of it. He's been like that since I changed his water 2 days ago. Which is also when I got two new snails to put into it. He eats like he normally does but he is no longer active. Kinda looks a little pale. Swims normal when he does move but rarely moves from the top of the tank. He's not gasping for air. But I can't tell if his gills are moving at all. He's a really dark blue. Can someone help me, possibly?

[ChoclateBetta]

Water quality changes need more info.

[aokashi]

Hi there we need more information about your tank such as

what temperature is it?
How often do youdo water changes?
how much water do you change out?
how much do you feed your fish?
do you know the
PH
ammonia
nitrite
and
nitrate levels in your tank?

you're saying he sits on top of the filter?