Guppy's Spot Appearing And Disappearing - Daily!

We have a guppy fry, well it's about a 1 1/2 month old now. Anyway, he has started developing a beautiful tail and colouring, but in the evening we lose him. At the feeding frenzy we can never find him yet in the morning there he is.

We have sussed it. Half way along his body towards the bottom he has a small black spot on both sides of his body (I tried taking a pic but he's a bloody fast mover). During the day it's very dark, almost black but we have spotted him tonight and it is now a very pale brown colour and can only just see it. Does this happen? I didn't think they could change their spots!!!!!!!

Could it possibly be the lighting? At night I have to turn on the light in one of my tanks to really get a good look at the fish, and gravid spots disappear, bceause of how bright the light is and the angle.

Nope. It's black black again this morning and the sun is only just coming over the mountain. Very weird!!

That's interesting. I've noticed this with a few of my fish, but they've "stabilized" within a few days. Are you feeding different foods?

Hi all

I've attached a photos of the guppy in question, it's a little out of focus but you can see the spot. This is during the day, so imagine at night that it's almost gone. Very very weird.

We have various dry foods, no live food as our supplier has not been able to get any for us yet. (we live in Bulgaria, it's not the UK or USA where you can get anything you need) so we vary the dry food, we have lots of varieties.

Well it will just have to remain a mystery

I have a guppy who has 2 disappearing, perfectly circular black spots on symmetrical sides of his body! They come and go during the day. My guppy is 4 months old and still getting his color, so I attributed it to his color coming in. I'll let you know if the color seems to stabilize!

Fish lose coloration at night, especially when resting. Not all, but with guppies and hoplos this is what I've experienced. I think I also saw my veiltail bettas going paler at night but it was long ago I had those.