Darned Amano Shrimp!

My female amano shrimp are around 2 inches long and the males are maybe 1 to 1.25 inches. I don't know if there is a magic number for a group but I have 5. They do like to hang out together under a plant or on a rock.
 
amanos do seem to hang out together. I currently have 6 in a planted 10gallon tank with sand substrate. Over the past several years I've had to replace 3-4 due to old age.

The females get quite big, some about 2 1/4" long not including antennae. The males stay much smaller, some only about an inch or so.

Amanos seem to live a long time and grow relatively slowly. Some of mine have to be over 3 years old at this point. Great, great little peaceful tankmates. The only thing is that they are greedy eaters and sense the introduction of algae wafers and other food in the tank right away. If you have more passive eaters like otocinclus, this could be a problem for the otos getting enough to eat.

how big do they get? and how many do u need in a group?
 
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