Tripod1404
Active member
Hello Guys,
Yesterday my neighbor (who started a sw tank after falling in love with mine), asked me if a reef tank is the hardest possible aquarium to keep. Well to his surprise I said a black-water planted discus tank is harder
.
About 15 years ago I tried to built a 150 gallon black-water planted discus tank. For those of you who are not familiar with such tanks, it is a fw aquarium mimicking the black-water affluents of amazon river (such the rio negro ) .
The water is black-tea colored, pH is around 5.5 and general hardiness is between 1-3dKh. You need to use dried leaves and wood to provide tannin color, Tank needs to be dimly lit (like the forest floor) and it should have low/ one directional flow (like a small stream).
For fish I had wild red discus (not the crap they breed these days, real thing from amazon), heckel discus and altum angelfish (not the regular freshwater angel fish but a close relative, Pterophyllum altum). I also tried to keep fish like cardinal tetras but failed (I will explain below).
Okay here comes the hard part;
First of all maintaining water chemistry was super hard. We are talking about a tank with pH 5.5 with nearly no carbonate buffering (very soft water). Buffering agents added to the tank (mainly organic acids), either decompose or get consumed by plants and etc. So you constantly need to maintain pH. Tank also need CO2 for plants, but if you over-do it pH can drop below 5.5. So CO2 should run during the day, but turnoff during the night (or a CO2 doser based on pH is required). For most places, hardiness of tap water is higher than 1-3dKh, so I used RO/DI water. Again, you need to adjust the pH of the water before adding.
And lets talk about the fish. Discus are cichlids and even the ones selectively bred for generations are not the most peaceful fish. Now multiply that aggression 10 and add the social structure of wild discus. In wild, these fish live in shoals of paired fish. So when they are not breeding they form shoals but each fish have their own partner in that shoal. During breeding season the shoal disassociates and pairs claim separate territories to breed. During breeding they become very aggressive. This works well in a river but in a tank you end up with unpredictable fish. One day they all get along fine and the next day there is a territorial battle. I tried my things to prevent inducing breeding behavior, like not adding cold water to the tank. But whenever it rained outside, fish became more aggressive (in wild they breed after rain when the river swells). Fish fighting in a tank with dry leaves and hummus soil as substrate, do not mix well. I had regular mud storms due to fish fighting. This sometimes also clogged the filters... Surprisingly different discus species do not shoal. I have never seen a heckel discus and red discus to form pair (although, I guess it is possible if there are no discus from their own species since there are hybrids). But they sure fight... Altum angels were another problem. They were considerably peaceful, but these guys consistently ate every small fish I added (such as the cardinal tetras). After some time I stopped adding small fish.
I later sold the tank to a fish store for a good sum. It was a nice tank but required a lot of attention.
So what are your experiences with other types of hard aquariums.
Yesterday my neighbor (who started a sw tank after falling in love with mine), asked me if a reef tank is the hardest possible aquarium to keep. Well to his surprise I said a black-water planted discus tank is harder
. About 15 years ago I tried to built a 150 gallon black-water planted discus tank. For those of you who are not familiar with such tanks, it is a fw aquarium mimicking the black-water affluents of amazon river (such the rio negro ) .
The water is black-tea colored, pH is around 5.5 and general hardiness is between 1-3dKh. You need to use dried leaves and wood to provide tannin color, Tank needs to be dimly lit (like the forest floor) and it should have low/ one directional flow (like a small stream).
For fish I had wild red discus (not the crap they breed these days, real thing from amazon), heckel discus and altum angelfish (not the regular freshwater angel fish but a close relative, Pterophyllum altum). I also tried to keep fish like cardinal tetras but failed (I will explain below).
Okay here comes the hard part;
First of all maintaining water chemistry was super hard. We are talking about a tank with pH 5.5 with nearly no carbonate buffering (very soft water). Buffering agents added to the tank (mainly organic acids), either decompose or get consumed by plants and etc. So you constantly need to maintain pH. Tank also need CO2 for plants, but if you over-do it pH can drop below 5.5. So CO2 should run during the day, but turnoff during the night (or a CO2 doser based on pH is required). For most places, hardiness of tap water is higher than 1-3dKh, so I used RO/DI water. Again, you need to adjust the pH of the water before adding.
And lets talk about the fish. Discus are cichlids and even the ones selectively bred for generations are not the most peaceful fish. Now multiply that aggression 10 and add the social structure of wild discus. In wild, these fish live in shoals of paired fish. So when they are not breeding they form shoals but each fish have their own partner in that shoal. During breeding season the shoal disassociates and pairs claim separate territories to breed. During breeding they become very aggressive. This works well in a river but in a tank you end up with unpredictable fish. One day they all get along fine and the next day there is a territorial battle. I tried my things to prevent inducing breeding behavior, like not adding cold water to the tank. But whenever it rained outside, fish became more aggressive (in wild they breed after rain when the river swells). Fish fighting in a tank with dry leaves and hummus soil as substrate, do not mix well. I had regular mud storms due to fish fighting. This sometimes also clogged the filters... Surprisingly different discus species do not shoal. I have never seen a heckel discus and red discus to form pair (although, I guess it is possible if there are no discus from their own species since there are hybrids). But they sure fight... Altum angels were another problem. They were considerably peaceful, but these guys consistently ate every small fish I added (such as the cardinal tetras). After some time I stopped adding small fish.
I later sold the tank to a fish store for a good sum
. It was a nice tank but required a lot of attention. So what are your experiences with other types of hard aquariums.
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