Microbe Mix is a natural mixture of mirobes and enzymes recommended for regular use in your composting toilet. Microbe Mix will help establish and maintain the speed and efficiency of your SunMar toilet; simply add a scoop every 2?3 weeks. Microbe Mix is available individually on this page, or in cases of 12 here. From the manufacturer:

Microbe mix contains dried aerobic microbes and enzymes which have been specially selected to help breakdown waste in Sun-Mar composting toilets. Non-toxic 100% natural product which is not harmful to humans, animals or the environment. This 16 oz. (454g) jar of bacteria allows you to increase the bacterial population and hence the composting activity. Ideal for adding at spring startup in the place of topsoil, which may not contain the proper bacteria needed for proper composting action.