How many different species in a given tank?

I'm sure nobody has a solid answer, but as I was staring at my tank wishing I could take a swim around in it, I began to wonder how many distinct species of creature, no matter how small or few, exist in my tank. I began to just count the individual creatures and it became too tough to count.

I am going to guess around 120 distinct species. Anyone want to shed light on this mystery or make a guess?

 

i'd guess you have more than that in just different bacteria, then add phytoplankton, pods, feathdusters, worms, etc etc etc! i'm gonna have to look it up! Want me to spoil it for ya?

 

i cant find a good answer! Stupid interwebs!