Plastic floating spheres by top fin

[squirley]

I am so happy with these floating plastic balls. The shrimp play with them and in this photo they are fastend to each othe with a vine of crypt!! When the shrimp grab onto them they spin and the shrimp can easily move them around

 

[GaryE21 19]

Once upon a time they were filtration media - dirt cheap in bulk. It's funny to see them recycled as shrimp toys.