Laboratory quality, one liter (approx. one quart) capacity polycarbonate Imhoff cones are used extensively in the brine shrimp industry to maintain consistent and reproduceable results when hatching brine shrimp egg. Recommended for hatching one to two grams of cysts. Imhoff cones are not free standing and require external support. A stainless steel rack that holds one to three Imhoff cones, available at Brine Shrimip Direct, works exceptionally well when positioned near a heat source - a 100 Watt incandescent bulb - or in a well-lit, warm environment. Another attractive alternative is to place cones in a constant temperature immersion bath. This is easily constructed by drilling 3 1/2" diameter hole(s) in a piece of 1/4" acrylic or Plexi-glass, which is then placed over the top of a heated aquarium. The Imhoff cone simply and safely nests in the hole and is easily maintained at the desired temperature, producing excellent results. Note: A 3 1/2" Hole-Saw, protective eyewear, clamps, care and adult supervision are required - or, lacking the above, a local glass supplier will often pre-cut and drill the acrylic at minimal charge. Aeration is supplied to the Imhoff cone(s) by use of an external aerator. Flexible air tubing connected to an 18" length of plastic rigid tubing (Both items available at Brine Shrimp Direct) is an elegant, yet simple solution for directing air to the bottom of the cone. Directing air to the bottom of the cone keeps the cysts in suspension and effectively eliminates dead spots where cysts might settle. The rigid tubing also eliminates the need for clips or attachments. We've found that the best way to harvest the baby brine shrimp at the end of the incubation period is to remove the air tubing, allow the brine shrimp to slowly settle to the bottom and, using a separate length of flexible air tubing, periodically and gently siphon the brine shrimp out of the cone into an intermediate container. Care must be taken that the baby brine shrimp do not become too densely packed at the apex of the cone and suffocate. Harvesting brine shrimp in this manner, as opposed to using a cone or apparatus wherein the shrimp are drained directly from the bottom allows one to better control and to minimize the amount of unhatched egg or empty shell that is transferred into the intermediate container and subsequently into your aquarium.