Isopods as a vivarium cleanup crew: choosing a species and keeping the colony fed
Written November 2026 by Lone Star Leaf Litter, the family business that keeps this archive online.
We sell Texas live oak leaf litter, and leaves come up in this article because isopods eat them. Weigh our preferences with that in mind, and check the advice against the care sheet for the animals you keep.
What isopods do in a vivarium
Isopods are small land crustaceans, the same group as the woodlice and pill bugs under a garden log. In a planted vivarium they eat what would otherwise pile up: fallen leaves, soft wood, droppings, shed skin, dead feeder insects and some mold. What they pass feeds the soil and the plants.
They are usually kept alongside springtails. Springtails are far smaller and work on mold and fine debris, while isopods handle the larger pieces. The two do not replace each other.
Isopods are also food. Dart frogs and small geckos will eat any they can catch, which is a useful extra for the animals and a constant drain on the colony. Most of what follows is about keeping the colony ahead of that drain.
Match the species to the enclosure
There is no single best isopod. Pick for the moisture level of the tank and for the size of the animals living in it.
- Dwarf whites (Trichorhina tomentosa) are the usual choice for warm, humid tanks such as dart frog vivariums. They stay under half a centimetre, spend most of their time down in the substrate, and reproduce without males, so a small starter group can build a colony. They need constant moisture and do poorly in dry setups.
- Dwarf purples are kept the same way and are often reported to multiply a little more slowly than dwarf whites.
- Powder blues and powder oranges (Porcellionides pruinosus) are mid-sized, fast and soft-bodied. They cope with a wider range of moisture than the dwarfs, so you will see them recommended for crested gecko tanks, for dart frogs and, with a damp retreat, for drier enclosures.
- Dairy cows (Porcellio laevis) are large, breed quickly and have a strong appetite for protein. Keepers disagree about them. Some use them with snakes and larger lizards. Others keep them out of shared tanks, because a big, underfed colony may chew plants and is reported to bother small or soft-bodied animals. With frogs, froglets and small geckos, the cautious choice is to leave them out.
- Pill bugs (Armadillidium) and many of the showy species sold as pets tend to eat soft plants, and some breed too slowly to survive being hunted. They are better kept in their own box.
If you are unsure, start with a dwarf species in a frog tank and a powder in a gecko tank. Many keepers run a dwarf and a powder together so that one works below the surface and the other above it.
Let the colony settle first
A handful of isopods tipped into a tank with hungry animals often disappears. If you can, add them when you build the vivarium and give them a few weeks before the animals go in. In a tank that is already occupied, release them under leaf litter or a piece of bark, and expect the colony to take longer to show.
A starter culture of a couple of dozen is a common starting point for a small to medium tank. More helps, but cover and food matter more than the opening number.
Give them places the animals cannot easily reach:
- a deep, loose leaf layer over the substrate
- flat pieces of cork bark or wood lying on the soil
- a corner that always stays damp, even in a drier enclosure
Isopods breathe through gill-like structures that have to stay moist, so they die quickly if the whole tank dries out. They also do badly in soil that is waterlogged. A range from damp to merely moist lets them choose.
What the colony eats
The staples are dead leaves and soft, decaying wood. Both should be in the tank all the time, not offered as a treat. A colony with plenty of leaves has less reason to turn to your plants.
Hardwood leaves are what keepers use most, with oak and magnolia named more than any others. Tougher leaves last longer as cover and thinner ones are eaten sooner, so a mix gives the colony food now and shelter later. Lone Star sells live oak leaf litter, and we go through the options in our notes on which leaves suit an isopod colony. Leaves you collect yourself work too, as long as they come from ground that has not been sprayed.
Cork bark makes a good hide but breaks down too slowly to count as food. For eating, isopods want wood that is already soft and rotting.
Extra food: protein, vegetables and calcium
In a tank with animals, droppings and dead feeders supply part of the diet. Whether you need to add more depends on how many isopods you have and how much the animals leave behind. When you do feed, feed small.
- Protein. A pinch of fish flakes, dried shrimp or a prepared isopod diet about once a week is common practice. The larger Porcellio species want more protein than the dwarfs.
- Vegetables. A thin slice of squash, carrot, zucchini or cucumber, washed or peeled first. Fruit is eaten too, but it molds fast and draws gnats and fruit flies.
- Calcium. Isopods need calcium to rebuild their shell after each molt. A piece of cuttlebone or some crushed eggshell left in the tank covers it.
Offer only what is gone in a day or so and take out what is not. Leftover food is the usual cause of mold, mites and gnats, and in a frog tank the simplest rule is to feed the isopods less often than you think you should.
Keep a spare culture
Animals that hunt through the leaf layer can wipe out a colony, and dwarf species in particular are hard to count. A backup culture outside the tank costs little.
A plastic shoe box with a few air holes is enough. Add a few inches of substrate that is moist but not dripping when squeezed, banked higher at one end so there is a wetter side and a drier side. Cover it with leaves and a piece of bark, and feed it the same way as the tank. When the vivarium colony looks thin, move over a scoop of substrate with the isopods in it.
Signs to watch
- You never see any. With dwarf species this is normal. Lift a piece of bark or look after dark before deciding they are gone.
- Leaves vanish quickly. The colony is large and well fed. Top up the leaf layer before bare soil shows.
- Plants are being chewed. Check that there are leaves and soft wood to eat, add a little protein, and consider whether the species is the wrong one for a planted tank.
- Numbers crash. The usual causes are a tank that dried out, soil that stayed waterlogged, or animals eating them faster than they breed. Fix the cause, then restock from the spare culture.
From the archive
Forum members were already using woodlice and pill bugs as tank janitors between 2006 and 2014, mostly under their garden names. These threads show how they went about it: