5-gallon betta fish tank

[bettacarehub786]

I have a 5-gallon betta tank with a sponge filter and a heater set to 80°F. My betta is active, but I’m struggling with keeping the water parameters stable. I do weekly 30% water changes, but ammonia sometimes spikes slightly. Any tips on keeping the water more stable in a small tank?
I searched different blogs. It really helped especially the bettacarehub.com but still want to know your personal thoughts.

 

[Windy]

Is your tank cycled? Do you have live plants in your tank? When you do water changes, do you syphon the gravel to remove waste? What are the water parameter results for the slight ammonia spikes? What water conditioner do you use?