Goldfish color fading & returning

[WILDCARD]

I bought a 60 gal. tank and put it outside with 2 goldfish, 1 koi and 2 shubunkin's with no heater or aquascape, bare except for 2 clay pots. It was outside for 1 or 2 months before i brought it inside and added a heater and the 4' flourescent light that came with it. All the fish were fine with the light on or off. After a month or so i added rocks, plants and stuff.
Thats when it started........whenever i turn the light on since then, they all hide in the corner for the first 5 minutes or so then come out, but each time, 1 of my shubunkin and 1 of my goldfish's colors have faded. But if i turn the light off, after about 10 minutes or so their color comes back. Mostly they lose their blacks and dark orange coloring but not the red's. The silver on my shubunkin also becomes semi-translucent, like you can see through the first layer of scales.

I know as goldfish age they fade in color, but mine are only 6 months or so old and this happens everytime i turn the tank lights on and off.
Any ideas?

 

[dkpate]

My fish are also faded in the morning after it has been dark. I was told on here that this is normal and most fish fade at night.

 

[jsoong]

Gold fish have the ability to change their color. <This is in addition to the usual color change with age.> They have limited ability to change the size of their melanophores (skin cells with black color) so they can be somewhat lighter or darker. They do that to match their surroundings. <A bit of residual camouflage ability.> The fish will show their color best when you have a dark background.

You see that mostly with black & blue colors. They are unable to change the orange/reds much. Goldfish are not nearly as dramatic as my hillies. They can appear pure white with tiny black dots on a white surface, all the way to pure black with tiny white dots on a black surface .... really quite amazing to watch.

As to the fish freaking out with the light, this is because of the abrupt change. They are used to the gradual brightening & darkening of sunrise/sunset. They might get used to the artificial light eventually. <Esp. if you have it on a timer so it is on at the same time each day.> A trick that might help is to have the light comes on gradually. SW people have multiple banks of lights/LED's & soft start ballasts so the light level goes up & down gradually to simulate nature. We can simulate that on the cheap by having a smaller room light that gets turned on a bit before the main tank light.

 

[WILDCARD]

Thanks to both of you for your responses. Its good to know the fading is normal.
Although i dont understand why they didnt do it when the tank was bare, and just started doing it only after i aquascaped it.
As for the light shock, i've tried to minimize it like you suggestes by turning on the room light, then opening the window shades, it helps some, thx.

ANOTHER QUESTION: My albino mickey mouse swordtail had 2 or 3 babies 2 weeks ago or so. Now she's fat again and is very protective of a certain spot in the tank and she chases most of my other fish away when they get to close to it. Could she be pregnant again/still without being with a male since she gave birth last time?
I ask because i've heard some creatures can keep having babies after only being with a male once by storing up his sperm.

 

[mfdrookie516]

yes, it is very possible. Im not sure if all livebearers do this, but guppies and platys do i know. I have two red wag platys in my tank that have had 3 batches of fry since i bought them and they are both female with no other males in the tank. And a suggestion on lighting, i have a floor lamp from walmart with a desk lamp about 2/3 of the way up... i shine that light on my tank if i need to do a pwc or something after dark so that i dont "scare" my fish too much, then after a few minutes, i turn on the light and they seem fine... just a thought