freshwater sponge

I have a small colony of freshwater amphipods living in my canister filter. They on a piece of freshwater sponge that I was trying to grow. Unfortunately, the sponge have died. I think that it had starved to death. It got smaller and skinnier over time. I am guessing that my tank was...

I went to collect some gobies for my Dniester Biotope project and guess what I found? A real life freshwater sponge or Spongilla fluviatilis. I have heard of freshwater sponges, but until now, I have never seen one. This is what I have noticed on a pieces of wood. At first, I thought that...