Glowlight Danio Behaviour

[kyleb2003]

I have a shoal of 10 Glowlight Danios in my 4ft/240l planted. First time I've kept one ofthe Danio species so hopeful some people with more experience can shed a little light here.

I started with a group of 7, they were always shoaling in various places, mid level, and came up for food no worries, added another 3 from a different shop that joined the group and were a bit more colourful (yellow sheen over the body that the adults posses). I then noticed that usually I'd have a group of 7/8 shoaling in the middle but quite low down towards the back, they come up for food and dash back down to that spot or recede into the plants if I walk to close to the tank, I rarely see them anywhere else, just in this middle area, whereas before I'd see them go side to side.

I have also noticed that when there's the group of 7/8/9 in the middle, the other 1/2 is below it, very near the gravel and behind the wood under the plants 'hiding', swimming around still but not coming out in the open or dashing back in if they see me, and always showing incredibly bright yellow colours. They sometimes come up to feed with the group but usually not for long and swim very rapidly and go back behind again. They stick out like a sore thumb with the colour difference, very yellow whereas the others are all darker with very little yellow. I thought maybe the colour and location could mean they were spawning but this same behaviour has been going on a fair few weeks now. I wanted to add a couple to the shoal but not sure if I should.

Any ideas?

 

[KittyKat]

Are the groups separated by colour? How many fish of which colour do you have? Can you take a video of this behaviour? Did you change anything at all around the time you added the 3 newest fish? Water parameters?

 

[kyleb2003]

No it's mostly just one big group of the same colour, then 1 or 2 of them that are hiding are very bright in colour. So yes they are separated by colour - but there's only really one group then the 1 or 2 away from the group, hiding, but brightly coloured. So it's a shoal of approx 8 normal colour, then 1 or 2 on their own bright colour.

I'll try to get a video later although the behaviour when I'm in front of the tank changes as they think they're getting food. Watch this space.

I didn't change anything at the time of adding the 3, and no major changes since. I had the 7 in there and put 3 more in about 2 weeks after and I've had them a couple of months now, I think they've been doing this at least a month. They still eat though, and are all still alive, so I don't understand the behaviour.

 

[MBOU]

To be honest, its how i always found glowlight danios to behave, they are nothing like the more surface dwelling zebras or leopards.

They do split up, scatter, shoal, split a different way, meet up, split up, shoal seperately, shoal together.... going backwards and forwards between behaviours over the day.

I also found (i had 25) that i always had a 'bachelor' group of males that usually ended up 'sauntering off' on their own, one dominant and a few very submissive malkes with the group of females but the older males split off on their own a lot of the time.

 

[kyleb2003]

Thanks MBOU, and did you have any that were bright yellow compared to the others? They all have a bit of a yellow sheen to them but one of them in particular looks like one of the aliens from cocoon.