We are undertaking an ambitious amphibian project with Atelopus barbotini, the purple toad. These funny little toads require exceptional attention to detail in their care requirements, with three specific setups used to simulate all phases of their lifecycle. We started our rack with a forest vivarium, then plan to add a stream vivarium, and 40 breeder sump grow out for tad rearing. This will be a complex build that we will track here, as well as the requisite photos of this incredible species.

We started our Atelopus barbotini project with a 0.0.4 (suspected 3.1) of captive bred individuals from Indicator Species. This was an exciting opportunity for us to setup a breeding group based on captive bred stock.

Note: Special thanks to Nick Stacey at Indicator Species. He was the first person to successfully produce Atelopus barbotini in captivity. He’s been instrumental in providing critical care parameters about this species to me, which are documented here, and show up in the design elements of the habitat build.

Classification of our little purple toad:

kingdom	phylum	class	order	family	genus	species
Animalia	Chordata	Amphibia	Anura	Bufonidae	Atelopus	barbotini

We have quite a few frogs, but A. barbotini is our first toad! And purple to boot. So what is the difference between frogs and toads? Setting aside the internal differences we cannot see, the main observable differences between our purple toads and our dart frogs are:

• spawning – our frogs deposit clutches in clumps, while our toads deposit strings of eggs.
• walking versus hopping – our frogs tend to hop, while our toads tend to walk.
• agility – overall our frogs are quite a bit more agile, while our toads are a bit more clumsy.

photos of Atelopus barbotini

Atelopus barbotini care information

Atelopus barbotini enclosure construction

Atelopus barbotini forest build

Our initial build was forest vivarium with no available water sources. This 18″x18″x24″ heavily scaped and planted vivarium serves as the main grow out for our group and will be a rotational viv when combined with the stream build. The plan is to move animals from a forest environment to a stream environment to simulate their breeding movements in the wild.

This vivarium is built out with a foam background coated in drylock. The false bottom is constructed of egg crate diffuser supporting a drilled acrylic plate that is covered with solar window screen. This allows for sufficient drainage.

My soil mix is composed of equal parts of:

• horticultural charcoal
• coco block
• milled sphagnum peat moss
• long fiber sphagnum moss

This mixture works well for me supporting a strong population of microfauna including dwarf isopods and springtails in this particular build. I use about 1 to 2 inches of soil, typically thicker in the rear of the vivarium.

I use a thick layer of live oak leaf litter. I prefer about 2 inches of leaf litter in the front of the vivarium sloping to 3-4 inches in the rear. This provides a strong starting point for litter to provide cover for the microfauna to establish themselves and begin breaking down the litter.

I focused on ferns and ficus for this build, as I wanted leafy plants on the ground level for ample cover, and epiphytic plants for the background to provide climbing surfaces and a lush canopy to again throw shade on the lower portions of the viv.

foam hardscaping

This is the initial phase of the hardscaping, where foam panels are cut and carved into shape, and gaps are filled with great stuff foam:

The branches are also made of closed cell foam. Strips were cut and shaped with a wire brush. A heat gun was used to tighten the surface of the foam, and while the foam was warm, it was bent in random directions to resemble more natural twisting branches.

foam texturing and painting

Once the branches were shaped they were attached to the main foam background with great stuff. The excess great stuff was cut back, and the entire background was then coated in brown tinted drylock, followed by successive dry brushed coats of lighter shades of brown:

Atelopus barbotini vivarium planting

Once the hardscaping was completed a layer of soil was added, then seeded with dwarf isopods and springtails. This was followed by adding a layer of leaf litter, then planting:

The following plants were used:

• Selaginella uncinata, peacock rainbow selaginella
• Ficus pumila ‘Variegata’, variegated creeping fig
• Arachniodes standishii, upside-down fern
• Pellaea rotundifolia, button fern

The selaginella and ficus were planted on the back wall, and are intended as an epiphyte that will cover the main background. The upside-down and button ferns were used on the floor of the viv to provide additional cover. Our group of Atelopus barboti spend most of their time in the leaf litter and among the ferns.

Atelopus barbotini stream build

Atelopus barboti breed in small streams with strong currents and clear water. I decided to use an Exoterra 36″W x 18″D x 18″H vivarium for this build. I didn’t need the height since the main focus of the vivarium will be on constructing the stream without a false bottom.

Stream viv foam work

I continued the use of closed cell foam to create the false bottom across the back half of the viv. I used silicone and black great stuff to fix the panels in place and secure cork rounds into the foam design. I also used great stuff to create a berm along the front to retain substrate. I carved this foam with razors and a kitchen knife.

Once the foam was carved, I began coating the foam with tinted drylock. I used a base charcoal tint then three shades of brown to provide depth and to better integrate the foam and cork bark.

Stream construction

Return and drain design

Lid construction

Atelopus barbotini sump growout build

The third component of construction was a location for tadpole grow out. In this case, since Atelopus barboti demands high quality water conditions, I decided to combine the stream build and tadpole grow out by using a sump design that links and expands the overall water volume of our Atelopus barboti breeding setup.

We are using a 40 breeder style aquarium which has a similar footprint to the Exoterra terrarium we chose for the stream build. This arranges nicely in the custom built cart we are using to showcase these animals.

internal filter

The internal filter / return side of the sump is on the right. There will be a tower return filled with filter floss managing mechanical filtration that sits above a bed of porous media that will handle biological filtration. Water will then overflow through the main weir that is blocked by a filter foam to prevent any tadpoles or toadlets from getting into the filter. This begins the flow from right to left to the return pump.

return chamber

The return chamber houses the return pump. It is isolated from the grow out section of the sump by a full height wall of corrugated PVC. A pass through at the bottom of the return chamber allows water to move from the grow out section to the return section. This pass through houses a piece of filter foam that will keep the tadpoles and toadlets out of the return.

With the build out complete, we can get a better view of the sump:

return plumbing and bypass

overflow design and plumbing

sump cover

Atelopus barbotini stand construction

The conceptual layout of this Atelopus barbotini display was to create a cart containing all three environments. The left side of the cart will be an equipment cabinet on the lower left, and an Exoterra 18″w x 18″d x 24″ tall forest vivarium for the females which will be moved seasonally into the stream build for breeding. The upper right will be a stream build housing the males in an Exoterra 36″w x 18″d x 18″ tall vivarium. The lower right will be a 40 breeder sump housing the flowing brook containing the tadpole grow out. Toadlet grow out (assuming we get the breeding cycle right!) will be off display in a configuration to be determined later.

Given this conceptual layout, the first step was to rough out a materials list and pickup some lumber. The build will be out of white pine boards. I decided to use 1″ x 2″ boards for most of the frame. I joined these boards with wood glue and screws to form the main vertical supports, using either 2″ x 2″ or 2″ x 3″ final dimensions. Based on my prior experience with stand construction, this framing method will be strong enough to support these vivariums. Upper non load bearing surfaces were supported with single 1″ x 2″ vertical members to keep the costs down. Overall, just under $200 in materials was used for the construction of this stand.

Atelopus barbotini lid design

Atelopus barbotini venting [materials on hand]

Normally I would not call out my vivarium vent designs, but I have been experimenting with new lid material in this build, and that has led to experimenting with new venting designs. I had two objectives in venting this viv:

• keeping the front glass clear, and
• generating some passive airflow in the back of the vivarium.

I decided to leverage my hole cutters to evenly space nine 35mm vents along the front doors, and two more 35mm vents in the rear of the viv. The exoterra 36″W x 18″D x 18″H vivarium has a vent built in below the door, so that will provide the passive air intake which will move up the glass to the 9 front vents, and back through the vivarium to the two rear vents.

So far, nothing fancy. So let’s throw together some 3D designs for vent grommets that can hold fly proof screens, keeping the flies out of the corrugations while keeping sharp screen edges away from the toads.

I mentioned earlier that I am using “Ninjaflex” filament – it’s a flexible filament that will provide flexibility to the vent grommet for easier installation. Additionally the screen cap will friction fit on to the grommet, providing a mechanism to sandwich a round screen within the vent. This should not require any adhesive, but I may use silicone to help fill any voids.

Atelopus barbotini lighting

Atelopus barbotini misting

Atelopus barbotini filtration and water quality

Some of this information may be redundant with the sump design, but I wanted to spend time discussing water quality measures taken in my habitat design, as this is a critical key to successful rearing of tadpoles based on conversations I’ve had with Nick Stacey, who has provided critical guidance that drove many of the design elements discussed here.

We will “follow the water” so we can see how the water quality is maintained.

water circulation

The main volume of water is maintained in the grow out sump. This is a 40 breeder aquarium that is about 1/4 full, for a total capacity of about 10 gallons of water. The sump is powered by a return lift pump. I’m using a Orlushy dc-9000 Silent Swirl Controllable DC aquarium Pump:

https://www.amazon.com/gp/product/B07C52Q4R1

I chose this pump because I wanted to experiment with a variable flow rate “wave” pump to see if it has an impact on the stream flow. This pump has two modes, steady flow and wave mode, with 20 different settings within each mode. Either way, there are plenty of sump pump options out there, this is just one that I chose to try out.

Key features of the plumbing include:

• Return “T” and ball valve
• Stream return
• Sump return
• Stream return chamber & overflow
• Stream overflow, drain chamber, and drain bulkhead
• Sump filter chamber
• Misting feed
• Forest drain return

Return “T” and ball valve

The lift pump is contained in the return chamber, isolated from the tadpole grow-out section of the sump by a 1 inch filter foam barrier contained in a custom build corrugated PVC board frame.

The return plumbing T’s within the sump, with a straight pipe running back to the filter tower intake. This straight return has a ball valve control that controls the split of water that returns to the sump versus returning to the stream. If the ball valve is fully open, all water returns to the sump. If the ball valve is fully closed, all water would return to the stream. Generally I try to target 25% of the water returning to the stream, with 75% returning directly to the sump.

Stream return

The stream return is a vertical section of flexible tubing that pumps water up the the stream vivarium on the left side of the vivarium. The tube connects to a section of PVC pipe with a 180 degree turn that runs the pipe internally down the back wall of the vivarium. Total vertical lift is about 3 feet.

Sump return

The sump return is a horizontal pipe that never leaves the sump. This is plumbed from the return chamber to the drain chamber where the filter materials are located. This straight return pipe has a ball valve that controls the rate of water flow return back to the filter.

Stream return chamber & overflow

There is an isolated return chamber within the left side of the false bottom of the stream vivarium. This chamber allows the pump to fill a chamber and spill over into the stream, providing a more even overflow. This chamber is separated by a closed cell foam wall with an embedded stainless steel screen covering the overflow.

Stream overflow, drain chamber, and drain bulkhead

The water flows through the stream bed from left to right, and settles in a small pool. A return overflow is cut into the false bottom bulkhead, again separated from the stream by a stainless steel screen. Behind this bulkhead is a return chamber. A drain was cut into the bottom glass panel of the vivarium within this return chamber. This 3/4″ bulkhead is fit to a flexible hose drain that plumbs into the sump filter chamber.

I did look at a variety of overflow design options from the aquarium hobby, but I thought they were a bit too sophisticated for my application, and, frankly, I didn’t want to risk drilling as much as would be required for something like a bean animal overflow. I’m only managing 10-15 gallons of water, and I’m not too concerned about periodic noise, so I went with a single floor drain design.

Sump filter chamber

This section has been discussed earlier. The right side of the sump contains a filter chamber. The back of the chamber is a tower where the sump and stream drains flow water into. The tower contains about a foot of filter floss during my initial design. I can change up the materials in this tower as needed, but these changes will be based on my experiences managing water quality as the setup ages.

The lower portion of the filter contains a large block of biological media. I chose 3.8″ ceramic block media for this design to minimize the width of the filter chamber. Here is a link to the media I used:

https://www.amazon.com/gp/product/B08PDLYSDY

The filter overflows a bulkhead and into the floor of the grow out sump. The ceramic blocks are separated from the grow out by another piece of filter foam that should keep the tadpoles and toadlets from gaining access to the filter media.

Misting feed

The misting system used to support the forest and stream vivarium planted land areas uses the sump as a reservoir. The misting pump inlet line feeds out of the sump return chamber. This pump drives a mist head in the forest build, and three mist heads in the stream build.

Forest drain return

Though tannins are our enemy in Atelopus barbotini tadpole rearing, I decided to go light on substrate in the forest and stream vivariums and plumb in the forest drain to the sump for a closed system. Given the use of UV sterilization, and an oversized filter chamber, I decided to experiment with both vivs draining into the sump to see if this filter and a regular water change regiment would negate the impact of these tannins on the system.

mechanical filtration

Mechanical filtration is achieved with a large block of aquarium filter floss that can be rinsed or replaced as needed.

biological filtration

As mentioned in the filter design section above, the sump filter is dominated by a set of 3.8″ ceramic blocks used to house beneficial bacteria.

UV sterilization

I decided to add a UV sterilization unit on the stream return based on a conversation with Nick Stacey, who stressed the key to successful tadpole rearing is crystal clear water conditions. He emphasized his use of a UV unit integrated into his canister filter, so I decided to augment my sump design with UV as well. I picked up a TetraPond UVC-5 in line clarifier:

https://www.amazon.com/gp/product/B00474BFSQ

Atelopus barbotini automation

lighting automation

flood prevention

misting cycle

Back to the main dart frogs page at oneillscrossing.com