These days, the Rubber Ducky
I mean, just look at them…
With their cute yellow duck faces and painted tails, they bring so much character (and usefulness to a terrarium).
Only recently discovered in Thailand, the new species – Cubaris sp. Rubber Ducky – was found in limestone cave areas so they have some unique care requirements compared to other isopods.
Find out where to find these beautiful creatures for yourself and how to care for them!

This page may contain affiliate links that allow us to make a small commission (at no further cost to yourself). 💚 Thank you for helping to support the tribe!
Rubber Ducky Isopod Lifespan, Behavior and Growth
Part of what makes these critters so rare is that they’ve been quite challenging to breed in captivity. They can take a fair few months to reach maturity, so it can take a while to produce enough for breeders to sell.
These cuties will grow a little bigger than the typical terrarium dwarf isopods, but they should max out around 2cm long so they’re still suitable for most reasonably sized terrariums/culture bins.

They also seem to be quite shy, and there are plenty of worried Redditors asking if their broods are okay because they haven’t seen them much in weeks!
Thankfully, Rubber Ducky Isopods reportedly can live for years with good care. Though, with them only discovered in 2017, that doesn’t give us a lot of lifespan data to work with…
Where to Find Rubber Ducky Isopods for Sale
Well, here’s the real question…
While Rubber Ducky Isopods have been hard to find historically, the team at Rubberduckyisopods.com specializes in them (as you might expect by the name)!
They often have stock, so I’d definitely check there first. 👇
Other Cubaris Isopods for Sale
Interestingly, there’s a wide variety of new Cubaris species being discovered. In fact, the Rubber Ducky
So, if you’re curious (or can’t get stock of Rubber Duckies just yet) here are a few other cool species you can check out too.
- Cubaris sp. ‘Red Tiger’
- Cubaris sp. ‘Panda King’
- Cubaris sp. ‘Papaya’
- Cubaris sp. ‘Amber’
Rubber Ducky Isopod Care
With Cubaris sp. Rubber Ducky being a relatively new species, people have been experimenting a lot to find the best conditions to care for them.
These orange-faced beasties tend to prefer damper conditions, moderate temperatures of 70-80°F (21-27°C), and higher humidity – which arguably makes them an excellent fit for tropical terrariums.
Though granted, they’re typically kept as an isopod pet rather than a bioactive custodian.

The following recommendations are a curated mix of supplies, foods, and substrates that expert
Food
Rubber Ducky Isopods reportedly like/need quite a varied diet.
Though they seem to prefer natural sources of decaying wood or leaves (e.g., leaf litter) rather than scraps from your meals, you’ll likely still need to supplement their diet with a protein source and, ideally, some limestone (more on that last one later).

For protein, some people like to add dried fish, either whole (small ones like minnows) or in a flake form. It’s worth experimenting to see what they like, and start small, as you don’t want your terrarium full of rotting food.
👉 This crab meal product is a convenient way to tick all those boxes!
Substrate
Substrate recommendations mostly fall in line with typical terrarium mixes but with a few added supplements. Here are some personal recommendations from experienced
“25% coco fiber, 40% chunked rotting wood, 15% leaves, and, 10% dried sphagnum moss, and finally about 10% pulverized limestone.”
@Derposour on Reddit
The coco fiber and sphagnum moss will help to maintain the higher level of moisture they prefer, and the wood and leaves are their primary food source.

The limestone is an interesting one, though.
In order to accurately recreate their natural environment, people have been adding limestone to the substrate mix with great results.
Limestone is a sedimentary rock that’s made up primarily of calcium carbonate, which they use to build their exoskeletons. Thankfully for us, calcium carbonate is actually a common gardening supplement that often goes by the name of “Garden Lime.”
It’s typically used as a soil supplement to increase the pH for plants, but it’ll work a treat here.
Finally, with their shy nature, rubber ducky isopods seem to like a deeper substrate layer that they can burrow into. If you’re establishing them separately from a terrarium, you can use these great acrylic invertebrate enclosures from EZbotanicals.

Over to You
Have you been one of the lucky few to get your hands on the Rubber Ducky
Let us know how you’re getting on in the comments!
Or, for more funky
Hey, since we don’t know much about this species since it was only discovered a few years ago, I thought I might say that I got babies from my Rubber Duckies. I noticed them yesterday, two months after I bought the parents. One of the females must have already been pregnant, but I figured it was also possible that they might have somehow reproduced quickly.
Congrats! Thanks for sharing, it’s always good to hear anecdotes for these kinds of things.
Just ordered 5 today!
I have 9 and they FINALLY had babies. I use dolomite mix and a cuttle bone for my isopods…I also make a isopod mix that is hard wood pellets (untreated) spagnam moss topsoil (organic) dolomite, and ground up leaf litter (i harvest from a local swamp that doesnt use pesticides) I had 7 months and noticed babies yesterday!
I saw 1 baby after 2 weeks of getting duckies, not sure if there’s any more. Unfortunately 1 adult passed away 2 days after I noticed mancae. It’s hard to say the reason, 5 of them seems to be full adult, not sure their age, maybe they are old. Hopefully it wasn’t environmental cause and I won’t see any more deaths.