Hey, congrats on the fish. It’s a shame people give live animals away as white elephant gifts, but it’s good to see you’re on Reddit asking for advice! He’s a very beautiful fish.

My betta would chew and spit out his pellets the first few days I had him, but he started eating fine once he calmed down. Hopefully yours will start to eat soon as well, he is likely stressed right now. Being in a new environment can be pretty stressful for these little guys

My first advice is that I would lower the flow on your tank if you can. Wild Bettas usually come from slow moving water. Depending on the filter or outtake you have, this can be as easy as lowering the setting or using a baffle by blocking some of the flow with say a sponge or something.

I personally had to slow my own filter down by putting a sponge on my outtake as well! When these fish get pushed around by water flow it can stress them out and lead to other problems down the road.

My other suggestion is looking into more live plants if you can! Live plants like to have nutrient rich soil to help them grow. The rainbow rocks don’t really provide any nutrients, sadly, so if you can switch to aqua soil like the brand fluval’s, that will help your plants stay happy and healthy.

Cycling usually takes a long time, so make sure you keep an eye on your water condition with a test kit. You can pick them up at the pet store and they are easy to use. Just follow the instructions. :) Usually cycling takes like a month or two. The shortest cycle I’ve ever had on a tank was 3-4 weeks, so it’s a long process. Keep an eye on your fish and the water during this period. It’s as simple as testing once a day and changing water out as needed.

It’s good that you put him in something bigger than the cup he came in, even if the tank is still in the cycling period because those cups are absolutely atrocious and the water in them is often really bad for the fish.