Yellow neocardinas seem suddenly frantic

[Kevin1962]

Hi all,
I have 15 yellow dwarf shrimp in a well established 10g with plants, flourite black sand, spider wood and a fine sponge filter.
6 have been in the tank for 3 weeks and 9 for 4 days.
Parameters:
Temp:78.6 (usually around 77)
pH:8.2
Amm:0
Nitrite:0
Nitrate:0 to barely reading
The shrimp suddenly began swimming around to the point of seeming frantic. I checked the parameters a few minutes ago (above). The pH at my tap is 8.0.
I added 2 small (1x1 cm) pieces of cuttlebone last week thinking the additional calcium can only help the little critters.
As there is abundant biofilm and algae I have fed very sparingly (tiniest pinch of algae and regular flakes every 4 days (last one yesterday).
10-15% water changes every 4 days.
Is a sudden change in activity normal?

 

[Demeter]

Probably males looking for a female that just molted and ready to breed. Check the genders of the ones swimming around.

 

[StarGirl]

My Neos swim all over the place too. I don't think you need the cuddlebone with 8+ ph. I have 8.2 pH also and never had to add anything.

 

[Kevin1962]

Probably males looking for a female that just molted and ready to breed. Check the genders of the ones swimming around.

Ah. Thank you!

Probably males looking for a female that just molted and ready to breed. Check the genders of the ones swimming around.

Yep. All males with a freshly shed molt sitting under the filter.

 

[redmare]

I'll second the guess of males looking for a lady friend. The first time I saw that in my shrimp tank I was super freaked out as well! But it means you should hopefully have some berried females soon.