ProRep Beetle Grub (Type B) | Beetle Larvae Food Substrate

PR Beetle Grub (Type B) is a specialist food substrate designed for rearing beetle larvae in captivity. Beetle grubs have highly specific nutritional requirements that cannot be met by standard substrates — they depend on the presence of white fungus, a naturally occurring fungus that breaks down cellulose and lignin from plant material into a form larvae can actually digest and absorb.

What's in Type B

PR Beetle Grub (Type B) is composed of hardwood chips that have been deliberately infected with white fungus and left to mature. This maturation process is essential — it allows the fungus to fully colonise the material and convert it into a bioavailable food source. This differs from Type A, which is based on prepared broad leaf tree leaf litter, and the two types are intended to be used together in varying ratios depending on the beetle species being reared.

Why White Fungus Matters

Without white fungus, beetle larvae cannot utilise the cellulose and lignin present in wood and leaf matter — these compounds are otherwise indigestible to them. By providing substrate already colonised with the correct fungus, PR Beetle Grub (Type B) removes the guesswork and gives larvae the nutritional foundation they need to develop properly.

How to Use

Mix PR Beetle Grub (Type B) with PR Beetle Grub (Type A) in proportions suited to the species you are keeping. Different beetle species require different ratios of the two substrate types, so research your specific species before setting up the enclosure. Both types are prepared and ready to use straight from the packaging.

For keepers rearing beetle larvae seriously — whether as feeders or as display invertebrates — using a correctly prepared, fungus-infected substrate like this makes a tangible difference to larval survival and development.