Questions about phytoplankton and rotifers

TylerInThailand · Jul 30, 2018

So I read online, and it seems that every site I saw says that you have to breed/culture the phytoplankton and rotifers outside of the aquarium or place in which they will be used. So typically I see a setup for phytoplankton and another for rotifers, the rotifers eat the phytoplankton and then the rotifers are eat by the stuff in the main aquarium.

I was wondering why that is necessary. I read that phytoplankton can be taken out through the protein skimmer, but I've also seen builds that do not include a protein skimmer. Is it not possible to then setup your tank in a way that phytoplankton and rotifers would reproduce naturally as they would in the ocean and then provide food for the ocean life within your tank?

This seems to be a no based on the lack of materials online I find for setting up such a tank, but why is that the case? What is the issue(s) you run into?

DeniseAndy · Jul 30, 2018

I have cultured phyto and rotifers for a short time. Trying to do this in a main running reef system is impossible because you have no way of knowing what is actually growing and eating. Most people do this when they raise fry so they have the rotifers as a food source and the phyto as the rotifers food source.

I am sure a mature and healthy reef system does have a nice culture of phyto, rotifers and many other planktons and "bugs". I will culture phyto to feed my system keeping the plankton and "bugs" that eat it happy and living. I do not mess with any others because I am not dealing with fry or any other specifically dieted creature. I will do artemia at times for a treat. That is about it.

So, IMO, it does happen in a growing, mature, healthy reef system. However, they are grown separately for when the person needs specific organisms fed, i.e. fry.

Brew12 · Jul 30, 2018

TylerInThailand said:
Is it not possible to then setup your tank in a way that phytoplankton and rotifers would reproduce naturally as they would in the ocean and then provide food for the ocean life within your tank?

I can find rotifers in my system using a microscope, along with different types of phytoplankton. I'm not sure the issue is that they won't reproduce. It is that they won't reproduce in your tank in large enough numbers to be significant.