Shrimp going crazy after lights on

[dao]

Hi everyone,

 

So. strangest thing ever lately happening in one of my tanks.

Since around a week or maybe a bit more the shrimp are acting stressed after the lights turn on. It's not instantly after the lights go on, but about after 1 hour or so. All shrimp stop grazing and start swimming around the tank restless to finally calm down after 30-60 mins more or less. It doesn't matter male or female, small or big all act the same like there would be some massive shift in water chemistry, but I have no idea what could it be.

 

So when I first saw this I used active carbon couple of times and thought that it helped as the shrimp have returned to grazing over time, but now I don't use it any more and they also do calm down after a while. No deaths so far, and the shrimp don't twitch when swimming around.

Does anyone have an idea of what could be happening?

 

Thanks

[ImBoB]

No idea... but my snowballs do it aswell, i just turn the light on 7 hours so its enough for my moss to grow, rest of the time light is off and they seem less stressed that way

[Shrimple minded]

To me this sounds like molting followed by mating activity.  Many refer to shrimp "dancing" as the males are in search of the freshly molted female.  

[dao]

Yeah, however i can see no berried females, plus i don't think that juvenile shrimp would also be doing that, right?

[pastu]

My juveniles Join in regardless, fun to watch

[Greenteam]

You can add shaded areas for them if you feel the light is stressing them out.