Betta discoloring

Question
I just got a new tank, it's been set up for about a week
It's two gallons
I have one Beta
I change his water weekly, doing a complete water change

The first thing I noticed was that the area around his head had really dulled, it turned from blue to brown. It looked almost like his scales had been rubbed off. A couple days later I noticed he had some red markings on each side of his body where his gills are. They don't look like sores, they are stripes about the width of a nickel and there's two on each side of his head. They also appear to turn white when he is not in the light, because in the morning they are a shiny, silvery white color, after I've turned the light off for the night, but then in the afternoon after a couple hours of sitting in the light they are red again. Just this morning I noticed he looks paler in color, but I suppose this could be the same problem with the light. I'm just not really sure if this is normal for a Beta, he is eating normally and he doesn't just lie around the tank, he's a pretty active little guy. Thanks in advance.

Answer
Hi Marissa;

He's probably fine. It's normal for fish to fade while the lights are out. They become darker again after the lights are back on for a little while. The head area has less color and the skin is thinner there so it is noticed more. The light on his tank may provide some heat too. When it is turned off the water cools a bit and causes fading color too. Make sure it doesn't drop below about 72f though. Keep an aquarium thermometer in there to check the temperature in the morning when you turn the light on. If the temperature drops too much at night you may have to leave the light on all the time. It doesn't hurt to do that. Many experts believe fish have to have a "rest time" to "sleep", but many others say it isn't necessary. I've left many of my tank lights on all the time over the years. Our aquariums served as "night lights" when our kids were little. The fish didn't seem to have any trouble with it.

Have fun with your new little friend...

At Your Service;
Chris Robbins