Mourning Gecko Vivarium: A Nano Bioactive Colony

The short version

• The mourning gecko (Lepidodactylus lugubris) is the only common gecko you keep in a group, because the species is parthenogenetic: every animal is female and lays fertile eggs with no male.
• A small group lives in a planted 12 by 12 by 18 inch vivarium at 72 to 82 F and 60 to 80 percent humidity, on room temperature with no heat lamp.
• Build it bioactive: a drainage layer, ABG mix, leaf litter, and a springtail-and-isopod crew that both cleans the tank and feeds the geckos.
• It is a genuine colony that grows on its own, which is the appeal and, in a nano viv, the thing you have to manage.

A mourning gecko (Lepidodactylus lugubris) is the only common gecko you keep in a group instead of alone, because the species is parthenogenetic: every animal is female and lays fertile eggs with no male involved. Put two in a planted 12 by 12 by 18 inch vivarium and, given time, you have a self-replacing colony rather than a single pet.

That biology makes the mourning gecko one of the best first bioactive animals. It is tiny at 3.5 inches, it runs at room temperature with no heat lamp, and it eats the same micro-insects a planted viv produces. Here is the enclosure, the parameters, and the bioactive build that feeds it. If you are new to the layered enclosure, read the full bioactive vivarium build alongside this.

Why the mourning gecko suits a nano viv

Most reptiles want space, heat, and solitude, and the mourning gecko wants none of the three in the usual way. It stays under 4 inches, it lives in a group, and it holds at 72 to 82 F, which in most homes is just the room. No basking bulb, no large enclosure, no single-animal rule.

The colony is the draw. Because the species reproduces without males, a starter pair becomes a small group over a season or two, laying pairs of hard-shelled eggs glued into the enclosure. That makes a mourning gecko viv feel alive in a way a single animal does not, and it is why the 12 by 12 by 18 inch nano footprint works: you are keeping a few small animals, not one big one.

The enclosure and parameters

Every number here comes from the compatibility database record:

Parameter	Mourning gecko (Lepidodactylus lugubris)
Enclosure	12 by 12 by 18 in for a small group
Temperature	72 to 82 F, room temperature
Humidity	60 to 80 percent
Adult size	3.5 in
Group	2 or more, all female
Diet	prepared diet plus micro-insects

The enclosure is taller than it is wide because the geckos are arboreal: they use vertical space, climbing the background and the glass. A front-opening 12 by 12 by 18 inch terrarium with a screen top is the standard, big enough for a small group and small enough to plant densely. Keep it out of direct sun so it does not cook past the top of the range.

The bioactive build, layer by layer

Build it the same way as any tropical viv, sized down. Bottom to top:

1. Drainage layer: LECA, 1.5 to 2 inches. Clay balls hold excess water below the soil so it never goes anaerobic.
2. Barrier mesh. A screen over the LECA keeps the substrate up top and lets water drain through.
3. ABG mix, 2 to 3 inches. The planting and cleanup-crew layer that holds moisture and stays open for years.
4. Leaf litter, a full cover. The crew's food and cover, and part of the forest-floor look.
5. Background and plants. A cork or foam back wall packed with sphagnum, planted with climbers.

Golden pothos (Epipremnum aureum) is the plant that does the most work here: low light, 65 to 85 F, and it roots into a background and strips nitrate fast. Its leaves are toxic if eaten, which does not concern an insect-eating gecko, but keep the enclosure to plants that suit the shade and humidity. A vivarium LED grows the plants; pair it with misting, because a bright light and a screen top dry the air.

The cleanup crew that also feeds the geckos

This is where a mourning gecko viv earns the word bioactive twice over. The crew cleans the enclosure and doubles as live food, so the same animals close two loops at once. Seed them two to four weeks before the geckos.

Tropical springtails (Collembola sp.) at 68 to 82 F and 70 to 100 percent humidity graze mold and become a snack the geckos hunt as they surface. Dwarf white isopods (Trichorhina tomentosa) at 70 to 82 F break down waste and leaf litter down in the substrate. A small gecko eats some of the springtails, the isopods handle what settles, and the litter feeds them both. You still feed the geckos directly, but the crew takes the edge off the waste.

Feeding and humidity

A mourning gecko eats two things: a prepared powdered gecko diet mixed with water, and small live feeders like flightless fruit flies plus the springtails the viv produces. Because the geckos are only 3.5 inches, the feeders have to be tiny, which is why fruit flies and springtails suit them where crickets would not. Feeders are usually dusted with a calcium supplement as routine feeding, which keeps a laying colony's bones and eggs sound.

Hold humidity in the 60 to 80 percent band with misting. By hand that is a spray once or twice a day; a misting system on RO or distilled water does it on a timer and keeps the glass from spotting. Let the enclosure dry down a little between mistings rather than staying soaked, and give a shallow water dish and the plant leaves the geckos drink droplets from.

The honest part: a colony you have to manage

The mourning gecko's best feature is also the one that bites beginners: it breeds itself. A group in a nano viv keeps laying, and a 12 by 12 by 18 inch enclosure that started with two geckos can be crowded within a year or two. Plan for it before you start, by having a larger enclosure, another keeper, or a shop ready to take offspring. A crowded nano viv stresses the animals and fouls faster than the crew can clear.

The other honest points are simple husbandry. The geckos hold at 72 to 82 F, so a hot windowsill or a summer room that climbs past the top of the range is a real risk, and there is no heat lamp to blame. Quarantine any new gecko in a separate, bare enclosure for a few weeks before it joins the group, which is the prevention that keeps one animal's problem from becoming the colony's. And a gecko that stops eating, drops weight, or looks off is a veterinarian's call, not a guess from a care sheet. None of this is set-and-leave: you mist, feed, watch the numbers, and manage the colony as it grows.

Frequently asked questions

Do mourning geckos need a heat lamp?

No. They hold at 72 to 82 F, which is room temperature in most homes, so a heat lamp usually pushes them too warm rather than helping. If a room runs cold, a low-wattage heat source on a thermostat set within that range is enough. The bigger risk is overheating past 82 F, not being too cool.

Can you keep a single mourning gecko?

You can, but the species is social and does best in a group of 2 or more, and since it is all-female there is no aggression from males to manage. Most keepers start with two and let the colony grow. A group also makes the animals bolder and more active than a lone gecko.

How big a tank does a mourning gecko group need?

A planted 12 by 12 by 18 inch vivarium holds a small starter group, with the height mattering more than the floor because the geckos climb. As a parthenogenetic colony grows, plan to move up in size or rehome offspring. Crowding a nano viv is the most common mistake.

What do mourning geckos eat in a bioactive viv?

A prepared powdered gecko diet plus small live feeders like flightless fruit flies, supplemented by the springtails and micro-insects the viv produces. The bioactive crew is a live-food bonus, not the whole diet, so you still offer prepared food and dusted feeders. Keep feeders small to match a 3.5 inch gecko.

Where to go next

A mourning gecko viv is a nano build where the enclosure, the humidity, the plants, and the crew all have to match one small animal. Read the vivarium humidity guide to hold the 60 to 80 percent band, leaf litter in a vivarium to feed the crew, and the vivarium background guide for the vertical space the geckos climb. When you are ready, run the enclosure through the build planner for a stocked, parameter-matched setup, compare the crew in the microfauna database, or read the rest of the vivarium guides.