brhau
Member
Hi all,
After taking a short break, I've started up my tanks again and I'd like to try building up a stable population of one of the described Parosphromenus species. I've kept softwater fish before, but never blackwater. So far, I have 4 tanks that have been running for about 6 weeks, 5 of those weeks with leaf litter, and about 4 weeks with plants. The surviving plants have really started to grow in the last 2 weeks, so I think I'm ready to add fish as soon as I can source the ones I want.
Here's my approximate stocking plan:
10-gallon tank: founder colony of 6 - 8 specimens, depending on species.
5-gallon tank: reserve for a breeding pair
15-gallon tank: growout
20-gallon long: display/community + growout. I plan to stock about 15 Boraras brigittae and hopefully 8 Hemirhamphodon tengah. I've tried to order the H. tengah already, but unfortunately the importer could not keep them alive. They're hard to get in the States, but I'll keep looking.
2.5-gallon: breeder or hospital tank
Water parameters:
Temperature: 23C for the paros tanks, 25C for the tengah
GH: 0
KH: 0
EC: about 50 us/cm
pH: 4.5 - 5
It's predictably difficult to stably maintain a low pH in these tanks. The resting pH of my RODI water is around 5.5. I can lower the pH to 4.5 by adding 2 drops of 1M sulfuric acid per gallon of RODI. However, the pH always drifts up due to the carbonate-carbonic acid equilibrium. To overcome this, I first add an excess of acid (for example, over 1 ml of acid per 10 gallons of aquarium volume) to neutralize the carbonate and move the equilibrium point lower. Once this is achieved, I add roughly 25% of that with each weekly water change to hold the pH between 4.5 and 4.8. The exact amounts are determined empirically and vary slightly by tank. Notes:
The 20-gallon tank theoretically houses 8 Tangerine tigers. They're smaller than breeding size, so in a crowded tank it's hard to confirm that they're still alive. I did see one last swimming about last week.
The 5-gallon tank has about 40 adult Asellus aquaticus. When I received them, there were about 50 tiny juveniles that I dumped in the tank as well. I have seen a few of those, though again they're hard to find amongst all the leaf litter.
Both of these species are prolific breeders, so I hope to distribute them to all the tanks eventually.
Plants:
I've tried a number of plants I thought would survive in blackwater and that might be appropriate for the environments. It was rough going in the beginning, as they all experienced some form of shock moving from whatever lush farm they came from to my blackwater tanks. But a few are really starting to settle in, albeit with smaller leaves, etc.
Successes (consistent new growth):
Salvinia natans
Salvinia auriculata
Salvinia minima
Ceratopteris thalictroides - Oddly, this is the first time I've gotten this to grow. Who knew I just needed to try blackwater?
Failures:
Pistia stratiotes - These melted right away. I don't think I'll try them again, as I don't think I ever use enough light to keep them happy. I end up with a million tiny leaves that are hard to collect and throw away.
Ceratophyllum demersum - I actually did get this to grow, but I don't like the extent to which it routinely sheds needles. That's not the type of bioload I want.
Azolla filiculoides - I naively ordered some of these not knowing how small the leaves are. I had duckweed flashbacks and decided not to use it.
Pushes:
Hydrocotyle leucocephala - It's growing, but shows clear deficiencies. It's also from the wrong continent (as a few of these plants are) but I added it in the beginning when nothing else would grow.
Süsswassertang - It looks fine, but I don't know that it would ever tell me if it's unhappy.
Vesicularia montagnei - It looks fine, but I don't know that it would ever tell me if it's unhappy.
Microsorum pteropus (Trident) - Grows too slow for me to tell.
Bucephelandra spp. - Grows too slow for me to tell.
Still trying:
Phyllanthus fluitans - These didn't survive the initial shock, but I'm going to try them again. There are a couple leaves that look healthy still, and the tank has matured a lot since I first added this.
Rotala H'ra - Just got these stems and haven't added to a tank yet.
Here's what the display tank looks like now. The other tanks aren't scaped or anything, they're really just holding tanks for plants. Will update you as things progress!
Cheers
After taking a short break, I've started up my tanks again and I'd like to try building up a stable population of one of the described Parosphromenus species. I've kept softwater fish before, but never blackwater. So far, I have 4 tanks that have been running for about 6 weeks, 5 of those weeks with leaf litter, and about 4 weeks with plants. The surviving plants have really started to grow in the last 2 weeks, so I think I'm ready to add fish as soon as I can source the ones I want.
Here's my approximate stocking plan:
10-gallon tank: founder colony of 6 - 8 specimens, depending on species.
5-gallon tank: reserve for a breeding pair
15-gallon tank: growout
20-gallon long: display/community + growout. I plan to stock about 15 Boraras brigittae and hopefully 8 Hemirhamphodon tengah. I've tried to order the H. tengah already, but unfortunately the importer could not keep them alive. They're hard to get in the States, but I'll keep looking.
2.5-gallon: breeder or hospital tank
Water parameters:
Temperature: 23C for the paros tanks, 25C for the tengah
GH: 0
KH: 0
EC: about 50 us/cm
pH: 4.5 - 5
It's predictably difficult to stably maintain a low pH in these tanks. The resting pH of my RODI water is around 5.5. I can lower the pH to 4.5 by adding 2 drops of 1M sulfuric acid per gallon of RODI. However, the pH always drifts up due to the carbonate-carbonic acid equilibrium. To overcome this, I first add an excess of acid (for example, over 1 ml of acid per 10 gallons of aquarium volume) to neutralize the carbonate and move the equilibrium point lower. Once this is achieved, I add roughly 25% of that with each weekly water change to hold the pH between 4.5 and 4.8. The exact amounts are determined empirically and vary slightly by tank. Notes:
- I've ordered some 10% phosphoric acid to use in rotation with sulfuric acid. The residual ions of these acids are both macronutrients for my plants, so hopefully this will lower my EC a bit and benefit the plants, which otherwise don't get any added fertilizer.
- My 20-gallon display tank is stubborn, and the pH rises much more quickly to a higher equilibrium. The only material difference between this tank and the others is the presence of a very large azalea root. I think the mistake I made here was waterlogging it in my RODI reject water. My tap water contains NaOH, so it seems I've added a sink of it that's continuing to neutralize my acid. I assume it will eventually exhaust. I do frequent, small water changes in the 20-gallon and the 5-gallon, since those have inverts in them. For the other tanks, I can still add the acid directly, only changing water occasionally to lower the EC.
The 20-gallon tank theoretically houses 8 Tangerine tigers. They're smaller than breeding size, so in a crowded tank it's hard to confirm that they're still alive. I did see one last swimming about last week.
The 5-gallon tank has about 40 adult Asellus aquaticus. When I received them, there were about 50 tiny juveniles that I dumped in the tank as well. I have seen a few of those, though again they're hard to find amongst all the leaf litter.
Both of these species are prolific breeders, so I hope to distribute them to all the tanks eventually.
Plants:
I've tried a number of plants I thought would survive in blackwater and that might be appropriate for the environments. It was rough going in the beginning, as they all experienced some form of shock moving from whatever lush farm they came from to my blackwater tanks. But a few are really starting to settle in, albeit with smaller leaves, etc.
Successes (consistent new growth):
Salvinia natans
Salvinia auriculata
Salvinia minima
Ceratopteris thalictroides - Oddly, this is the first time I've gotten this to grow. Who knew I just needed to try blackwater?
Failures:
Pistia stratiotes - These melted right away. I don't think I'll try them again, as I don't think I ever use enough light to keep them happy. I end up with a million tiny leaves that are hard to collect and throw away.
Ceratophyllum demersum - I actually did get this to grow, but I don't like the extent to which it routinely sheds needles. That's not the type of bioload I want.
Azolla filiculoides - I naively ordered some of these not knowing how small the leaves are. I had duckweed flashbacks and decided not to use it.
Pushes:
Hydrocotyle leucocephala - It's growing, but shows clear deficiencies. It's also from the wrong continent (as a few of these plants are) but I added it in the beginning when nothing else would grow.
Süsswassertang - It looks fine, but I don't know that it would ever tell me if it's unhappy.
Vesicularia montagnei - It looks fine, but I don't know that it would ever tell me if it's unhappy.
Microsorum pteropus (Trident) - Grows too slow for me to tell.
Bucephelandra spp. - Grows too slow for me to tell.
Still trying:
Phyllanthus fluitans - These didn't survive the initial shock, but I'm going to try them again. There are a couple leaves that look healthy still, and the tank has matured a lot since I first added this.
Rotala H'ra - Just got these stems and haven't added to a tank yet.
Here's what the display tank looks like now. The other tanks aren't scaped or anything, they're really just holding tanks for plants. Will update you as things progress!
Cheers
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