One Year Inside My Flooded Cave Ecosystem (Paludarium)

These fish don't have eyes, but they aren't the only strange creatures you can find lurking among the foliage. This is a story about biodiversity and how a series of unexpected changes turned this place into a thriving underground

ecosystem

. This project started with building a stand, because I needed another surface to support my aquarium addiction. There would be tanks at the top, storage at the bottom, and tanks in the middle. Or maybe a big tank... I couldn't decide. But I had all the materials taking up space for a long time, so at some point I chose a design and ran with it.

Usually something goes wrong at first when I'm setting up a project, but this whole build went surprisingly smoothly considering all my dumb design decisions and how cheap all the materials were. If it wasn't made from scrap metal, it was made from old furniture. For example, I found this second-hand table online for a great price and cut a piece off it. Then I used the rest as a countertop for other tanks and random things. Underneath I hooked up some normal overhead lights and then started building a tank. The previous owner left this one out in the cold for too long and it no longer held water.

So... they gave it to me for free and I was able to recycle the glass. I decided to make a large tank because I didn't want to miss the opportunity to make something strange and unique. But while I was putting it together I had no idea what direction it was going, or that it was going to take a whole

year

to mature. And if I had I probably would have made a lot of different decisions. However, I added a plastic roof on a whim to protect the lights from water. But in the end it was that choice that accidentally drove the whole design, because I thought, "If the tank has a roof, maybe I should just build a

cave

?" The surface of this lava rock is covered with small spots of dry moss and other signs of erosion.

I hope they add some character to the

cave

walls. I collected the root of this tree from the bank of a local river because I wanted something to build the landscape around. It's nice when a composition can tell a story, so I cut it to size and it became a perfect starting point. Instead of just putting rocks everywhere, it would provide a dynamic line that the eye could follow across the tank. I started by placing rocks around the root to give some motivation to its organic shape and because I wanted to paint the image of a tree root that had broken through the surface into a hidden cave.

Additionally, by keeping the hardscape off the bottom of the tank, you would be robbing the fish of less water volume in what is already a shallow space. When I was happy with the design, I sprayed expanding foam between the gaps so that everything would stay in place when I put the tank back upright. I also ran this plastic hose along the top corner, because a water source could explain why the cave is

flooded

. I hid the hose under the foam and after everything had settled, it was strong enough to hold all the rocks and wood without any chance of anything coming loose...but it was definitely ugly.

I knew from working with it before that if you cut into its smooth shell you'll find a spongy interior full of holes formed by air pockets, and they're not much different from those found in igneous rocks like the ones I'm using. . Even after sculpting the foam by hand, it wasn't as beautiful as the real rocks I was trying to imitate, but being on the walls and ceiling, it had to be as light as it was. Additionally, the product was designed to be used in ponds and fish, so it was also a convenient way to put everything together without introducing a lot of different materials and chemicals.

I wanted to hide the heater somewhere, so I left a space at the bottom left and buried it; with a bomb. I removed the foam with some scraps from the plastic roof, but in case the heater ever broke or the pump clogged, I opened it again and filled the void with some filter sponge. To hide the electronics even better, I drilled a hole in the ceiling to run more hose, but this time I ran the wires through. Finally, the DIY was almost finished. I just needed to put the tank in place and hook up the lights.

When I turned them on, the lights helped blend the different materials and it looked more like a believable place, but it was too clean...which is not ideal for the fish; They will not be the healthiest in a sterile environment. Therefore, building on a foundation of garden soil ensures that there is plenty of life at the bottom of the food chain for plants and microfauna to thrive. On top is a thick layer of sand to keep everything in place. It's also a medium for good bacteria to grow...and then, obviously, you need water. One of my other tanks is filled with Java moss, so I harvested a few clumps and used them to quiet the running water.

With a calmer soundscape, it is easier to notice and appreciate the softer sounds coming from the water. The introduction of plants raised a lot of dust from the very fine sand. but I quite liked the hazy atmosphere it created. With so much water and good bacteria in the soil, adding 20 small shrimp the first day was no problem for the system. These guys came from my other shrimp tanks with colorful shrimp inside. but after generations of mixing different lines, they begin to lose the bright colors they were created for. and I actually prefer the more interesting colors and patterns they develop because they are more like what they have in nature.

They all looked completely unique, so even after they had gone off to graze on the sand and rocks, I could still tell which was which. I deliberately left a handful of gaps and caves around the tank where they can go for darkness and privacy. In this half of the tank you can see the entrances to three caves, two of which are even connected by a tunnel, so the shrimp can do what they do for behind-the-scenes fun. There were now more than a hundred shrimp in the tank, maybe more than 200. And they all seem busy all the time, as if each one were an important part of the shrimping society.

Actually, I should say, they formed a society of crustaceans. Because among them there was a completely different species, which was a kind of ostracod. You could see many of them walking on the sand. Well, actually there were literally millions of them. Because when you install a new tank, there are a lot of things they like to eat; like algae and dead plants. I had just refilled the water that had evaporated during the first few months. And since the level was higher now, there was a lot of food on the menu that was out of my reach before. especially at the root of the tree, because it was directly under one of the lights.

All the plants and animals in the tank seemed to thrive. And there was nowhere you could look without seeing some kind of life. That said, there was still room for more shrimp, more plants, and a long list of other creatures. The water had crawled up the moss I added and resurrected a type of lichen on the porous rock. It ended up inspiring me to branch out even further, with a handful of plants I picked under a waterfall in the woods. I also got some leaf litter while I was there. I rinsed everything to remove mud and debris, then also soaked it to remove pests.

All of them came from a natural stream, in the moors where it originates. Therefore, they will be free of contaminants and anything else that could disrupt the system. There are mosses, grasses and a couple of leafy stemmed plants. Although I'm not sure if everyone will adapt to their new home, with less mud and slightly warmer weather. Dead tree leaves are probably the foundation of most freshwater

ecosystem

s, so it's no surprise to see all the shrimp coming out of the wood to get a taste. If you remember the ostracods eating the rotting plant bits in the tank, well, this is a layer of food that will also act as a home for all the different microscopic scavengers.

The shrimp love it and it will provide plenty of hiding places for what comes next... ...lots of Kuhli loaches. They hid for a while and then settled like a pile of scratched noodles in the grass. They are much more social than shrimp and also have much more personality. Getting settled didn't take long, with so much cover to hide in and so many friends to keep each other company. Touching and tasting everything with his weights seemed to be priority number one. Digging was next on the list and boy, do they like digging? I guess they mainly look for food, but they also dig little trenches to hide in, so I usually try to watch them from a distance to make sure they don't get suspicious and run away under a leaf.

But if you look closely you can see that they sift the sand through their gills. And they need more than just what's in the sand, so it's about time the first real food entered the system. Every shrimp in the tank stopped what he was doing almost immediately and scurried to the center of the tank to grab one of the pieces. Some of which were taken, even though there were plenty to go around. The protein-rich feast must have been very welcome because it wasn't long before the shrimp began to reproduce, which can be recognized by the males flying around frantically while the females just...relax with their eggs.

You don't see Kuhli loaches during the day because they are nocturnal, but after the lights go out, they are everywhere. They sift the sand looking for tiny particles of food that the shrimp will have left over from that day. But shrimp are active all hours of the day, so they never stop stirring and mixing that top layer of sand with bits of food, piece by piece. Additionally, they vary their own diet, alternating between sand and leaves. I saw a different type of creature moving in a corner. I think they are crane fly larvae. It will have come out of the wild moss I added and won't be harmful in any way, so I let it wander around the tank on its own.

I watched him meet up with some of his neighbors, and then he started trying to dig into the substrate... and eventually made some progress, but was taken away by a very curious loach. She crawled under a leaf and then, just like that, I never saw him again, so I guess she finally managed to hide underground. Or more likely it was eaten by one of these cheeky guys. A few weeks after covering the walls with plants, evidence of decay could be seen, but from all decay new life emerges. Because there is always something else in the food web that can benefit from decomposition.

The nice thing about a

paludarium

is that you have a section of land and you can see two different environments interacting with each other that we normally think of as separate. That said, it wouldn't be a complete ecosystem without something to fill the gaps above the water. So I added these isopods that will live in the moist moss, where they can help process any dead plants they find. and then you have these springtails that will live everywhere, so they will help stop mold growth. They are also small enough to walk on the surface of the water, so they can feed on biofilm and algae at the edges.

Then, as a bonus, I'm going to take some caterpillars that are attacking one of my plants in the kitchen, because instead of just exterminating them, I thought I'd move them to the cave where they would actually be welcome. . It could be that there aren't enough fresh leaves for them to eat, in which case they won't do well and will simply become food for something else... but I guess I'll know based on whether I see a cocoon there one day. Each species in this tank has its own role to play and hopefully each of them will multiply and reach a stable population over time.

There is already a great variety, but there are also things that are not on this list and that are too small to see with the naked eye. and soon I will add things that are much bigger than any of these. With all the new creatures, I needed a way to keep them contained. Most of them would have a hard time crossing the glass walls to jump, but they would probably try and I didn't want bugs all over the carpet. So I cut a piece of plastic from the same material as the roof and left a little space around the edges for air circulation.

It was actually a bit of a difficult position to fit the nuts and bolts from the inside. I don't know why this little guy decided that a piece of inert plastic had any value. But I had to confiscate it to finish the update. The moss around the running water was nice and juicy, but the parts with less humidity and less light were not as lush. So the door was not only to keep the animals in, but also to keep some humidity. Now the plants will stay hydrated and it will be a little warmer. I spent an embarrassingly long time trying to figure out how to keep the door open for access, and came up with about 10 different ideas, toocomplicated and twisted, then I realized I could just... hold it open with the other door.

To prepare for some new inhabitants, I decided to play 'smashy smashy' with some leftover lava rocks. There was a lot of open space in the middle of the sand bed, and I noticed that the Kuhli loaches were still shy about coming out into the open. I wanted everyone to feel safer and more secure when crossing to the other side, so I decided to evolve the waterscape a little. As usual, the shrimp came to greet the inanimate objects. I tried to form two focal points by making two piles of rocks with a natural location. Smaller pieces were scattered to mix everything together.

I then made holes on top of them just to suggest that the rocks had somehow collapsed from above. And so, there was a lot more coverage to help everyone feel safer. But in practice, your only potential threat won't be relying on line of sight. I am a simple boy. I just wanted to build a cave and fill it with fish that come out of the caves. These fish are blind because evolution took away their sight... and what look like eyes are actually just empty sockets. So your perception of the world comes from a line of sensory organs on each side of your body.

Basically, they don't hit things because they can detect objects through changes in water pressure. They don't have vision for the same reason they don't have brightly colored scales: they come from underground caves where there is no light. Then they can use that energy to be scary in some other way. Shrimp know to back away if they get too close, because these fish don't give off a friendly vibe. In the wild, they feed on insects like these bloodworms and crustaceans, and when you see the way they attack anything that's vulnerable, it's no wonder shrimp are so cautious.

Like these who share a meal without taking their eyes off the potential danger. Cave fish have no natural predators, so they see everything as their own territory and are therefore quick to get yelled at if you try to touch what's theirs. Even if they couldn't put a particular food in their mouth, they would still take it themselves. Let's say they definitely have anger management issues. I tried adding just one spirulina tablet and nothing else. They could smell that it was food, so they shooed everyone away and put it away, until they discovered that they couldn't actually break the pieces off by themselves.

These fish are opportunistic like most omnivores, so they will happily eat the plant-based foods I give them if they can... but they show their carnivorous side if they get the chance. Despite fighting voraciously over the body, I don't think they actually killed a shrimp. Cherry Shrimp has this special ability that allows them to teleport in the face of danger. With so many in the tank, I'd be willing to bet that the unfortunate one simply died of natural causes and the curious fish were excited to clean up the mess. I never saw this happen again, so I don't think it's in their nature to hunt this type of prey.

They're just defensive and curious, because I mean... they can't see what's going on :) The Kuhlis know what's going on, so they don't bother them at all. In fact, they don't even flinch, and the mother shrimpers are still happy to walk around outdoors carrying all their babies. The upper and lower parts of the tank developed in parallel, and the green covering of each slowly extended towards the center. There is a dividing line that separates the two worlds, but it also gives us a way to see how they reflect each other. Microfauna that play the same role in each system would be next to each other, feeding on the same algae, right on the edge.

Because almost all food chains start in the same place, at the same scale. A closer look reveals that they look nothing alike physically, although they eat the same things. Then, with an increase in size, we see a similar situation: two young scavengers living in Java moss. Both sides of the system have healthy diversity, but to be as strong as possible, they would need to talk to each other. and that can be helped with one last change in the panorama. By changing the larger rock for an even larger one, I want to break that barrier, literally breaking the surface.

The island allows the moss to absorb carbon dioxide from the air and fertilizers from the water. Then, with some ground plants anchored around the edges, the roots can work their way into the rock, binding everything together. And now that there were leaves on top, it was a good time to replace the ones on the bottom. This time using a larger and more useful variety. The bottom dwellers appreciated having a layer of darkness to disappear into... but mainly the leaves are there to release tannins into the water... because we're going to need them for the last new species.

I have some frogs. They are very cute little ones. And like all amphibians: extremely stupid. I was looking for animals that would fit well in the tank, when I read, "Vietnamese Mossy Frogs are found in

flooded

caves," so they really were the obvious choice. Sorry...erm...so...they really were the obvious choice to make the best use of the entire

paludarium

. They sit around all day pretending to be moss and ambush anything that comes their way. However, at night they go into hunting mode. and you can see evidence of them hanging around the tank, but they're definitely not being as sneaky as they think.

Once I start hearing random splashes and bangs, I know they're awake...and I also know exactly when they'll pounce on their prey...because when they're excited, their toes tremble. For some reason, one of them loves to climb on top of the others. And it usually causes a problem for all three of them. But it's not hard for them to eat, because the food usually reaches them, and even if they barely reach their goal, their sticky tongue seals the deal. Certain species of frogs can't or won't eat underwater... and while these guys like to take a dip every now and then, they don't show any interest in fish or shrimp.

Any other fish should be able to see the crickets and drag them under the water, but the blind fish can only find the ones that sink to the bottom. Frogs, on the other hand, can jump from anywhere and at any time. Being nocturnal, mosses like to make noise in the middle of the night. Each of them calls it a different thing, so I usually know which one is looking for attention. I was sitting here trying to record a voiceover and the frogs just kept saying: (frog call intensifies) Would you be silent for five minutes? Look at this little troublemaker...

Shut up! Thank you. Anyway, when I couldn't do voice over, I did some private live broadcasts for my clients. We basically sat and watched the frogs together, but most of the time we waited for something interesting to happen. Amphibians generally stay still for hours on end. And then when something finally happens, it's very easy to miss. Patience was the name of the game for this project, so a big thank you to everyone who waited and supported me while I worked on these tanks. Whether I'm there for the community or just to learn about natural aquariums, I appreciate all the people who share stories about their own stories.

In this one, the frogs have grown into these chubby little ammonia machines... and you can see it's done wonders for the plants that can absorb that kind of waste, but there's too much of it, so to keep things balanced. , I have to change the water... only every... three months or so. It might even have to be more frequent, if I'm lucky with the tadpoles the frogs spawn. The waterfall is covered in a thick layer of moss that cleans the water as it trickles into the forest below. There is a happy relationship that goes both ways, because plants absorb the waste from all the different creatures and use it to compete with each other for access to light.

However, leaves providing shelter support is just the beginning, as even dead leaves release useful compounds...while also providing a base...for the bottom of the food chain. Slow and steady adjustments to the environment can create the right conditions. So diversity in flora and fauna gives a system an answer for everything... so you have something strong and stable... in the end.