Beyond Leaf Litter: Specialist Diets for Isopods

While leaf litter will always dominate most terrestrial isopod diets, there are a lot of other foods that can - and for many species should - be added to the menu. Many keepers rotate several kinds of food on top of the leaf litter. This article covers the main supplementary food categories beyond standard leaf litter.

For the basics - leaf litter, decaying hardwood, and standard isopod husbandry - see our guide to setting up and selecting your first isopods. What follows is the next layer of dietary refinement once the basics are sorted.

Protein Sources

Isopods are more protein-hungry than most beginners realise - particularly the premium Cubaris and Ardentiella morphs. Keepers offer these species protein as a regular part of the diet, and many offer it to other species too.

The principle to follow is matching protein sources to what the isopod would encounter in the wild:

• For species near water bodies in the wild - fish-based foods. Shrimp meal, fish flakes, freeze-dried bloodworm, and aquatic protein blends are all suitable. Many premium Cubaris breeders use fish-meal-based foods as their primary protein supplement
• For species from drier habitats or forest floors - insect-based foods. Insect protein blends (such as Fluker's, Bug Bites, or similar) replicate the kind of dead-insect protein these species would scavenge naturally. Cricket frass, mealworm meal, and similar are all valid options
• Across all species - variety matters. Many keepers rotate between protein sources rather than relying on any single one

Frequency: most isopod keepers offer protein supplements once or twice a week. Some keepers offer protein more often to premium Cubaris and Ardentiella. Common species like Porcellio scaber and Armadillidium are more flexible and don't need protein as often.

If you're feeding meat-based products, make sure they don't go mouldy or off before the isopods consume them. Remove uneaten portions within 24-48 hours, especially in warm humid enclosures.

A Note on Feeding Isopods to Isopods

You may see some keepers feed culled isopods from one species or colony to another. The thinking is that this provides species-appropriate protein, and that since different isopod species aren't biologically the same animal, this isn't cannibalism in the strict sense.

Where we stand on this:

• It does happen naturally. Larger isopod species - particularly large Porcellio like P. expansus, P. magnificus, and similar - will opportunistically eat smaller isopods that enter their enclosures. This isn't unusual
• But deliberately culling for cross-colony feeding has risks. Cross-colony pathogen transmission is real. Isopods can carry bacteria, fungi, viruses, mites, and other pests that can devastate a recipient colony. What seems like a healthy donor colony may be carrying a pathogen tolerable to one species but lethal to another
• Standard protein supplements are safer - fish flakes, dried shrimp, insect-based protein, and similar give protein without the disease-transmission risk

If you do choose to feed isopods to isopods, only do it from a colony you've kept stable and disease-free for a long time, and only between species where this is biologically natural. The convenience isn't worth introducing a mite outbreak or bacterial bloom into a valuable colony.

Bat Guano: A Premium Cubaris Consideration with Significant Caveats

You may see bat guano recommended in some isopod hobby circles, particularly for the premium Cubaris. The reasoning starts from where sellers place these animals, the Thai and Vietnamese limestone karst, caves included; no hobby form has a published scientific description or collecting locality, so that is an account rather than a record. In a real cave bat guano does form the base of the food web, and the woodlice that live there feed on it.

However, bat guano comes with serious health and safety considerations that mean we don't recommend it for hobby keepers.

Histoplasmosis risk: Dried bat guano is a documented carrier of Histoplasma capsulatum, a fungal pathogen that causes histoplasmosis in humans. Inhaling spores from disturbed dried guano is a known occupational hazard for cavers, archaeologists, agricultural workers, and demolition workers handling old buildings. The infection can range from mild flu-like symptoms to severe lung disease in immunocompromised individuals. This isn't a theoretical risk - there are documented outbreak cases worldwide. Caving organisations, the World Health Organisation, and public health authorities all recognise it as a real hazard.

Ammonia concerns: Bat guano in enclosed spaces releases ammonia as it decomposes. In a tightly-sealed isopod enclosure, this can build up to levels that stress or harm the colony. The "spread thinly across substrate to let bacteria neutralise it" approach mitigates this somewhat but doesn't eliminate it.

Unknown source content: Commercial bat guano sold as fertiliser doesn't tell you which bat species produced it, where it was collected, or what those bats had been eating. The nutritional content varies substantially. Other contaminants (heavy metals from cave geology, residues from cave-floor microorganisms) may be present.

Our position: For UK keepers, we don't recommend bat guano supplementation. The histoplasmosis risk, ammonia concerns, and unknown content variation outweigh any dietary benefit claimed for it. Many keepers raise the premium Cubaris on standard protein supplements (shrimp meal, fish meal, insect-based foods), with no guano. If you're determined to build a diet around where these animals are said to come from, focus on calcium sources (limestone, cuttlebone), mineral variety, and high-quality protein rather than actual guano.

Repashy Gel Diets and Other Prepared Foods

Beyond protein supplements, many keepers add prepared gel diets to an isopod feeding routine. Repashy makes several products designed specifically for invertebrate keepers - sold as powders that you mix with hot water to create a gel that sets in the fridge. Once set, it can be portioned and even frozen to extend shelf life.

The two most relevant for isopod keepers:

• Bug Burger - a gel food made for feeder insects that many keepers also use for isopods. Suitable as a regular protein supplement, particularly for protein-hungry Cubaris species
• Morning Wood - made for isopods and other detritus feeders. Useful when your leaf litter stocks are running low

We stock both, and they're worth having on hand for variety.

Vegetable Matter and Fresh Foods

Fresh vegetables and fruit add moisture, micronutrients, and dietary variety:

• Vegetables - cucumber, courgette, sweet potato, carrot, kale, spinach, broccoli, butternut squash. All accepted by most species
• Fruit (occasionally) - apple, banana, melon, mango. Treats rather than staples. Leave out citrus, as keeper guides often advise
• Mushrooms and fungi - readily accepted; many isopods are keen on mushroom material given their natural diet of decomposing organic matter including fungi

Replace fresh food every 24-48 hours to prevent mould.

Calcium and Micronutrients

Keep calcium in the enclosure at all times: woodlice build a calcium carbonate cuticle. Multiple calcium sources work well:

• Cuttlebone - leave in the enclosure permanently and replace it as it is used
• Crushed eggshell - an occasional extra, sprinkled on substrate or offered in a dish
• Oyster shell flakes - similar function to crushed eggshell
• Limestone pieces - passive calcium source plus habitat enrichment

Many keepers also vary the diet beyond calcium. Mixing leaf sources (oak from one location, beech from another, magnolia from a third) is one way, and occasional protein supplements, fresh foods and prepared diets are another.

Browse our accessories collection for calcium and micronutrient options.

The Variety Principle

Beyond leaf litter, the aim is variety. Isopods evolved as detritivores eating whatever decomposing matter was available - they're adapted to varied diets rather than monocultures.

A practical weekly feeding rotation might look like:

• Continuous: Leaf litter, decaying wood, calcium sources (cuttlebone, limestone)
• 2-3 times per week: Fresh vegetable or fruit slice
• 1-2 times per week: Protein supplement (fish flakes, shrimp meal, or insect-based food)
• Occasionally: Mushroom material, prepared gel diet, sphagnum moss patches

This kind of rotation mirrors the dietary variety isopods would encounter in their natural habitats.

Where to Source Specialist Foods

For setup essentials and the bulk of your isopod feeding needs:

• Leaf litter - the dietary foundation
• Shredded rotten wood - secondary food and substrate component
• Cuttlebone - calcium
• Flake soil - nutritional substrate addition
• Full accessories range for protein supplements and other dietary additions

For Repashy gel diets specifically, we stock both Bug Burger and Morning Wood. Bug Burger is the one to reach for if you keep protein-hungry species like Cubaris or Ardentiella, and both are a useful supplement to the regular feeding routine.

The bottom line: leaf litter is the foundation, and many keepers rotate protein sources, fresh foods and prepared diets on top of it.