Amano Shrimp going nuts

[AmanoNoob]

Hello all, I have noticed that there are times my Amano shrimp just kinda go spastic running around the tank. Normally they graze the day away eating algae off my plants / decor within the tank but occasionally they all just flip a switch and start swimming around the tank crazily the whole population of them. All the while my small lot of tetras and raspboaras didnt show any behavior difference. But it was really noticeable that something was different for the shrimp. I am new to the hobby so assuming something was wrong with the water chemistry or building up within the tank I would do a 30-50% water change (with conditioner) and all the shrimp would seem to calm down and go back to grazing around the tank. I also tested to see if this was hunger induced so I tried feeding some shrimp pellets when this occurred but they simply ignored the offering until I changed the water.

I wanted to dig into this further so I got a bunch of quality testing strips and a full wet chemistry set to monitor my tank parameters more closely, and everything has been fine honestly. But I got home from work today and the shrimp were in full NASCAR race mode around the tank so I checked the water. No ammonia, no Chlorine, Nitrites were zero, and Nitrates were within safe levels around 10-20 ppm and pH was stable at 7.2 like it usually is. So everything I checked seemed to look absolutely fine but I changed the water anyways and everyone calmed down.... what the heck am I missing?

The only thought in my mind is perhaps instead of some chemical building up in my tank is there something like a trace element that the shrimp are absorbing from the water column that eventually gets depleted and they need 'fresh' water with what ever element my tank is now lacking? My local municipal water is actually very high quality, we have a large river running through town that's the main water source and tends to be pretty soft, with very little chlorine but I always add conditioner to be safe.

 

Ive had this tank for almost 6 months now, its planted as well and coming along nicely. The shrimp have done a great job of keeping it clean too! I have a good canister filter, slightly oversized for my tank, with better quality biological media than what comes with the unit. And my ammonia / nitrites are always zero so its got that part of the N2 cycle down but hasnt built up enough anerobic bacteria yet for the full cycle. Getting there though! So I have done my level best to setup a nice environment for my aquatic friends and it seems to be working except the shrimp go nuts every 8-12 days.

Looking for an education about what I am missing here, thank you very much for your time to any who reply. Thanks!

 

[Tracy]

Hello AmanoNoob....how many amanos do you have?  Everyone will tell you about the "dance" that male shrimp display when a female is ready for breeding.  How often are they behaving that way?  Is it just the males or is everybody acting like that?