Is it possible to identify the nearly microscopic critters in the water column? I have a few interesting 8 legged/tentacled critters that remind me of something like an octopus in shape...but sooooo tiny. I have video of one on the back of the tank if any one wants to try identifying it.
Looks like a Hydroids - Medusae (Mini Jellies) I had a lot of them when my tank was new they did not last long http://www.lionfishlair.com/hitchhikers-guide/
Agree with David! Some species can be a problem but I had those and they never seemed to bother anything. There are some larger ones we've encountered diving that can inflict some nasty stings.
