Recipe Cards for Preparing Food Paramecium Likes

There are many good media, but these are two old standbys that work

Wheat Grass Medium

Wheat Grain Medium

   

Put 2.5  grams of Wheat Grass Powder (see below) in 1 liter of water, bring to a boil, and boil for 5 minutes.

Filter through a Mr. Coffee Filter to remove the powder.  This works quicker with a vacuum filtering apparatus, but it isn't necessary. If you DO use a vacuum, you must take precautions to keep steam out of the vacuum pump.

Mix 100 ml of a 10 g/liter Sodium Phosphate (Na2HPO4) with 900 ml of the filtered solution.  Distribute into flasks and autoclave for 15 minutes at 15 pounds pressure with a slow exhaust.  I use 1 liter flasks and put 500 - 600 ml in each one.

The day before use, inoculate a flask with bacteria (Klebsiella aerogenes or Aerobacter aerogenes) and incubate overnight.  The next day the medium will be ready to add Paramecium to.  They grow best at 27o C. 

The medium will be cloudy when you inoculate but will clear up was the ciliates eat the bacteria.  Often a scum will form on the top.  For most of the exercises described in this web site, it will not hurt anything and is difficult to get rid of in any case.

Wheat Grass Powder can be obtained from  Pines Distributors International, P.O. Box 1107, Lawrence, KS  66044.

You can buy Wheat Grains and Straw from Biological Supply Houses like Carolina or Wards.  Use Spring Water, not tap water for this medium.  To about 10 - 20 wheat seeds and a little bundle of straw about 1.5 inches X 0.5 inches add 500 ml of Spring Water and boil the mixture.  Just bring it to a boil and then remove from the heat and let it cool.  

Add a culture of Paramecium to the mixture.  At fist the bacteria you transfer with the ciliates will brow faster and the medium will become very cloudy.  But then  usually the medium gets relatively clearer as the Paramecia reproduce and eat the bacteria. 

Sometimes these cultures will smell pretty bad, but if there are Paramecia in the culture, that's ok.  Infrequently the Paramecium will die out when a bacterium they don't eat very well grows in the culture and uses up all the oxygen.