I've kept aquariums on and off for many years. I hadn't had a bigger tank in several years, but after a lot of research, I decided to try my hand at creating a western upper Amazon tributary 'blackwater' biotope. The environment I'm replicating is a slow moving flooded forest edge. The water is very soft and acidic, and is stained a deep chestnut brown by all of the botanical material (leaf litter, branches, seed pods, etc) that leach tannins, humic acids, and other compounds into the water. These environments have little or no aquatic plants growing in them, but they do have riparian edge plants that grow their roots into the water, and floating plants that trail their roots in the water.
The tank is 80 x 35 x 40 cm, so 112 liter (30 US gallon) nominal capacity. Substrate is inert yellow-ochre sand. The hardscape is mostly locally procured branches of Portuguese cork oak and sycamore, with just a couple of anchoring pieces of aquarium store driftwood. Ordered a couple of types of Amazon seed pods, as well as adding locally sourced acorn caps and alder cones. Leaves are a mix of oak, magnolia, and catapa. Since the real environment is very low flow, and that's what the native fish like, I only have one very small external hang on back filter oriented so the flow is along the long axis of the tank. It's got some coarse foam in the outflow to diffuse the flow further. Most of the biological filtration is handled by the bacteria that colonize the copious roots and branches, the glass, and the substrate. A lot of research has been done in recent years that has upended a lot of conventional wisdom around aquarium filtration. Turns out we've been doing almost everything wrong for a lot of decades!
I intentionally allowed the tank to mature without any fish in it. That has several benefits, the main one of which is that in addition to allowing the beneficial bacteria, archea, and fungi to mature before fish arrive, you get a much more robust colonization. The result has been spectacular. The system is able to process 2 ppm of ammonia overnight, which is far more than a large school of fish is capable of creating. The riparian and floating plants also do a lot of uptake of ammonium and nitrate, helping with the whole process. The maturation period also allowed a thriving population of tiny organisms like copepods to spring up, which will provide extra food for the fish when they arrive. I've also had mosquitoes lay eggs, and I've seen their larvae (ultimately to be fish food, thank goodness), and some other small midge larvae, etc.
I got the idea to mount driftwood along the rim of the tank as a place to put the emersed peace lily. On the pieces that required it, I cut a shallow channel in the wood that fit down over the tank rim, and put a piece of silicone tubing cut lengthwise under it. Holes drilled and reamed out provide a place for the plant's crown to sit above the water, with the roots in the water.
The lighting system has really impressed me. I settled on a Chihiros WRGB II Slim light, and I'm blown away by the quality. It's Chinese, but it's totally top shelf quality. It's controlled via their app, and it gives you almost limitless ability to control the mix of colors, intensity, and best of all, the timing. You can set it to do a very realistic dawn and dusk ramp up/down period rather than just going from dark to light in one jump. Since this biotope is from an area with shaded light filtering through trees, I'm only using a small fraction of the light's output, but it's absolutely gorgeous in the tank.
My stocking plan is all geographically appropriate species. The first residents are a school of 20 Cardinal tetras which I bought in Porto on Saturday (not a lot of local fish stores in my area...). They've settled in nicely, and are busy exploring the tangle of roots and branches, and picking at the wood and the roots of the plants for the micro critters.
Next will come a small school of Corydoras duplicareus. They're on their way from a retailer in Spain, hopefully this week. The "centerpiece" fish will be a male Apistogramma agasizii. Eventually if I can find them, I may try to add some brown pencilfish (Nannostoma eques) to occupy the surface area of the tank.
Overall I'm extremely pleased with how the tank has come together. Being Portugal, boodles of patience is required to get all the pieces needed, but eventually it happens.
I've actually been using ChatGPT quit a bit to help me with this project, and I must say, it has really been helpful. Working on water chemistry, etc, it's been a huge boon.
I have to say - this forum platform has the dumbest handling of images I've ever seen. Nothing I do will put images into my post. It's like it's 1995 again.
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The tank is 80 x 35 x 40 cm, so 112 liter (30 US gallon) nominal capacity. Substrate is inert yellow-ochre sand. The hardscape is mostly locally procured branches of Portuguese cork oak and sycamore, with just a couple of anchoring pieces of aquarium store driftwood. Ordered a couple of types of Amazon seed pods, as well as adding locally sourced acorn caps and alder cones. Leaves are a mix of oak, magnolia, and catapa. Since the real environment is very low flow, and that's what the native fish like, I only have one very small external hang on back filter oriented so the flow is along the long axis of the tank. It's got some coarse foam in the outflow to diffuse the flow further. Most of the biological filtration is handled by the bacteria that colonize the copious roots and branches, the glass, and the substrate. A lot of research has been done in recent years that has upended a lot of conventional wisdom around aquarium filtration. Turns out we've been doing almost everything wrong for a lot of decades!
I intentionally allowed the tank to mature without any fish in it. That has several benefits, the main one of which is that in addition to allowing the beneficial bacteria, archea, and fungi to mature before fish arrive, you get a much more robust colonization. The result has been spectacular. The system is able to process 2 ppm of ammonia overnight, which is far more than a large school of fish is capable of creating. The riparian and floating plants also do a lot of uptake of ammonium and nitrate, helping with the whole process. The maturation period also allowed a thriving population of tiny organisms like copepods to spring up, which will provide extra food for the fish when they arrive. I've also had mosquitoes lay eggs, and I've seen their larvae (ultimately to be fish food, thank goodness), and some other small midge larvae, etc.
I got the idea to mount driftwood along the rim of the tank as a place to put the emersed peace lily. On the pieces that required it, I cut a shallow channel in the wood that fit down over the tank rim, and put a piece of silicone tubing cut lengthwise under it. Holes drilled and reamed out provide a place for the plant's crown to sit above the water, with the roots in the water.
The lighting system has really impressed me. I settled on a Chihiros WRGB II Slim light, and I'm blown away by the quality. It's Chinese, but it's totally top shelf quality. It's controlled via their app, and it gives you almost limitless ability to control the mix of colors, intensity, and best of all, the timing. You can set it to do a very realistic dawn and dusk ramp up/down period rather than just going from dark to light in one jump. Since this biotope is from an area with shaded light filtering through trees, I'm only using a small fraction of the light's output, but it's absolutely gorgeous in the tank.
My stocking plan is all geographically appropriate species. The first residents are a school of 20 Cardinal tetras which I bought in Porto on Saturday (not a lot of local fish stores in my area...). They've settled in nicely, and are busy exploring the tangle of roots and branches, and picking at the wood and the roots of the plants for the micro critters.
Next will come a small school of Corydoras duplicareus. They're on their way from a retailer in Spain, hopefully this week. The "centerpiece" fish will be a male Apistogramma agasizii. Eventually if I can find them, I may try to add some brown pencilfish (Nannostoma eques) to occupy the surface area of the tank.
Overall I'm extremely pleased with how the tank has come together. Being Portugal, boodles of patience is required to get all the pieces needed, but eventually it happens.
I've actually been using ChatGPT quit a bit to help me with this project, and I must say, it has really been helpful. Working on water chemistry, etc, it's been a huge boon.
I have to say - this forum platform has the dumbest handling of images I've ever seen. Nothing I do will put images into my post. It's like it's 1995 again.
View attachment IMG_0810.jpeg
View attachment IMG_0809.jpeg
View attachment IMG_0814.jpeg
View attachment IMG_0813.jpeg
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