Bettas behavior

Question
Hi, I've just got a betta from a friend earlier today. When I got it, the tank was very dirty, and the water was below average temperature. I've just changed the water, cleaned the tank, and added a plastic plant in the tank.

Now, the fish is a lot active than before. He swims very fast, almost like a dash. He also goes up for air more often.

I noticed he pushes his head in spaces between rocks, while his body faces diagonally/downwards. He remains like that for a few seconds, and then continue to swim around. He never did that before I changed the water. I don't have enough rocks to fill in the spaces in the tank.

Is it possible for him to get stuck between the rocks and damage himself, or suffocate? Is there anything I can do to help prevent it? And, is dashing around the tank normal? Usually, when I see bettas, they lie at the bottom of the tank, or swim at normal speed.

Answer
Hello Matthew-

A lot of bettas bury themselves in rocks, usually because they are curious or are looking for a "nest" to hide in. I had a female who used to do that all the time!

It's also normal for bettas to "dash" around, like what you are experiencing. Both behaviors are common when a fish is moved to a new, cleaner environment. Eventually, your little guy should calm down once he figures out where everything is in his new home.

These can also be symptoms of ammonia poisoning, however, and if your fish seems listless, has clamped fins, or is gasping for air (rapid gill movement) then you should change about 50% of the water daily until his symptoms improve.

Hope this is helpful!
-Amber Worman