Guess, that's true with regards to loss of biodiversity. Although there will be some organisms that turn up later on that will surprise you! I noted that with the feeding of live phytoplankton, you can sustain biodiversity for a much longer time.
I have tunicates, mini featherduster worms and sponges which keep growing as a result.
I used to have a lot of copepods in the past, than later on, the amphipods were the dominant species of pods in my tank.
I think we have to be mindful of possible predation & eradication of the 'little creatures' and taking care of them via feedings of the right food eg. phytoplankton, to keep biodiversity of microlife in our reef tanks.