This is the basic set up I am using. The large Rubbermaid stock tanks are being used to culture greenwater. The Moina (Moina macrocaopa) / Rotifer (Brachionus calyciflorus) cultures are in the 20 gallon "Muck Buckets" in the foreground. After taking this photo I have added 2 more 100 gallon stock tanks and a 1/2" PVC air line. The air supply is provided by a single Tetra Deep Tec 96/2 diaphram air pump. Each tank there is one small airstone.
Typically, I harvest 50% of the volume of each "Muck Bucket" and replace with new green water. The Rotifers and moina will (if given sufficient food, temp, and proper environment) double in population every 24 hours. Thus it is possible to remove about the same amount every day. At the point that I begin harvesting a culture, the rotifers or moina will clear the water (remove all green micro-algae) in this 24 hour period. Bear in mind that you wil need to concentrate the culture, replacing the animals that get collected when the water is changed. To facilitate changing and prevent the loss of rotifers or moina I use a 40-60 micron polyester screen ("NITEX" Florida Aqua Farms)to collect the rotifers and moina. See the diagram.
My greenwater source is several overstocked tanks with goldfish. They are fed OSI Spirulina Flakes and it keep the water green. I alternate harvesting over several cultures. Keep in mind you will need to keep the cultures going to a point where you will harvest 50% of the green water, and expect the culture to bounce back in a day or so.
