Fermenting forms a large part of my work. Here is some of the kit I use.
Incubation setup for small-scale koji making (or anything else that requires maintaining a constant temperature)
Inkbird ITC-308 Digital Temperature Controller Thermostat Dual Relays Heating Cooling 220V Plug
RINBO Seedling Heat Mat — There are lots of heating mats available, but I’ve found these ones to be reliable, waterproof and inexpensive.
Thermo Future DL988 Thermobox Eco
Places to buy koji spores from
USA: http://gemcultures.com/ (probably the best when you’re starting)