20 gallon high blackwater setup starring Betta dimidiata

Hi everyone! HUGE update...there are now at least five bettas in this tank! I just saw a juvenile, roughly three quarters of an inch long, near the front of the tank. The second time I went to look at him/her, they spooked and swam away...but clearly this tank is very capable of raising baby Betta dimidiata, even though I have not deliberately fed them any live foods in a long time (I chock it up to the enormous amount of leaf litter and accompanying microorganisms). I wonder how many other juvenile bettas are hiding in this setup, especially seeing how the males seem to spend more than half of their lives holding fry?

In other news...I have removed the light from the tank for now to combat continued problems with cyanobacteria, so it is currently quite dark.

 

Hi again everyone! Today was a touch madcap as far as this tank was concerned...I decided to remove all four adults temporarily so as to give all the fry in this tank the best chance of survival, but I had to remove all of the several gallons of leaf litter to find them. Needless to say the tank is a mess. On the plus side, there are at least five fry/juveniles in the tank ranging from about half a centimeter to more than half an inch in length, and I will grow these on in this setup for two or three months before repeating the above process and putting the adults back in here after removing all the fry. (The adults were added to a 5 gallon QT tank along with some leaves, fake plants, and filter media from the main tank, as well as a new sponge filter).

 

(The adults were added to a 5 gallon QT tank along with some leaves, fake plants, and filter media from the main tank, as well as a new sponge filter).

Make sure the tank has the same parameters, but honestly: I would have not moved any fish. Hope this isn't going to bite you back.

 

Make sure the tank has the same parameters, but honestly: I would have not moved any fish. Hope this isn't going to bite you back.

Oof! Now I am nervous most of the qt tank water was from the main tank...I was doing a water change at the same time.

 

Sorry, but you have to have a source of H+ in that tank to keep pH and at the same time humic substances to buffer in the low range. At least throw in a bag of peat!

 

Sorry, but you have to have a source of H+ in that tank to keep pH and at the same time humic substances to buffer in the low range. At least throw in a bag of peat!

The leaves do not suffice for the tannins? The main tank has a TDS of around 10-15 ppm depending on the day of the week (water changes for this tank consist of pure RODI water)...I've never had issues with tanks this soft crashing into alarmingly low PH ranges (in fact, I have repeatedly tried to get other setups to have PH values below 6-6.5 and consistently failed, with the PH bouncing back to the low to mid 6's within a matter of hours, presumably due to bicarbonates formed from the addition of CO2 to the water by gas exchange...my only tank that consistently stayed below that value was a five gallon licorice gourami tank I had once. It had several inches of peat moss on the bottom and I still needed to add sodium bisulfate to the new water to get the PH to 4.2...and it still rose to 4.8 by the next 40% weekly WC).

For those curious...all four adult bettas are alive, well, and eating in the quarantine tank, though they seem a little shyer than usual (maybe because it is a bare bottom tank without a background...I will freely admit that this was hastily set up, I should have planned this better, and that catching them from the main tank was one of the most infuriating tasks I have done in my entire aquarium keeping career).

 

The leaves do not suffice for the tannins?

Not necessarily in that newly setup tank.

The main tank has a TDS of around 10-15 ppm depending on the day of the week (water changes for this tank consist of pure RODI water)...

My TDS are higher (50mg/l) due to the fact I fertilize my plants, but I also use uncut RO.

I've never had issues with tanks this soft crashing into alarmingly low PH ranges (in fact, I have repeatedly tried to get other setups to have PH values below 6-6.5 and consistently failed, with the PH bouncing back to the low to mid 6's within a matter of hours, presumably due to bicarbonates formed from the addition of CO2 to the water by gas exchange...my only tank that consistently stayed below that value was a five gallon licorice gourami tank I had once.

Why do you think I imply a pH crash? I was thinking of a sudden rise!
CO2 gas exchange makes CO2 dissolve as carbonic acid, the amounts of hydrogencarbonates are negligible. But a smaller amount of humic substances can be the reason for a higher pH.

It had several inches of peat moss on the bottom and I still needed to add sodium bisulfate to the new water to get the PH to 4.2...and it still rose to 4.8 by the next 40% weekly WC).

It rose because you diluted the amount of humic substances (and sodium bisulfate additionally). It takes a lot of botanicals and a lot of time to get to a constantly high concentration. (I'm btw not looking forward all happy to my tankupgrade in January because of this. Took about a year to get down into the 4.x range.)

For those curious...all four adult bettas are alive, well, and eating in the quarantine tank, though they seem a little shyer than usual (maybe because it is a bare bottom tank without a background...I will freely admit that this was hastily set up, I should have planned this better, and that catching them from the main tank was one of the most infuriating tasks I have done in my entire aquarium keeping career).

Good to hear they are doing good.

 

Not necessarily in that newly setup tank.

My TDS are higher (50mg/l) due to the fact I fertilize my plants, but I also use uncut RO.

Why do you think I imply a pH crash? I was thinking of a sudden rise!
CO2 gas exchange makes CO2 dissolve as carbonic acid, the amounts of hydrogencarbonates are negligible. But a smaller amount of humic substances can be the reason for a higher pH.

It rose because you diluted the amount of humic substances (and sodium bisulfate additionally). It takes a lot of botanicals and a lot of time to get to a constantly high concentration. (I'm btw not looking forward all happy to my tankupgrade in January because of this. Took about a year to get down into the 4.x range.)


Good to hear they are doing good.

I can add a few more leaves to the QT tank if there is not enough to keep the PH down (I added roughly two dozen aged leaves when I set the QT tank up). The PH for the licorice gourami tank was 4.2 right after the water change and rose to 4.8 by the next weekly WC...I can definitely reduce water changes if I ever need an uber acidic tank again (these bettas have proven to be rather undemanding, though, so my weekly 3-4 gallon WC's on the main tank will probably continue).

 

After reading all this thread and being interested in black water tanks ( admittedly without the full knowledge to achieve this ) im invested, commenting to follow this journey with interest !

 

I can add a few more leaves to the QT tank if there is not enough to keep the PH down (I added roughly two dozen aged leaves when I set the QT tank up).

Well, aged leaves have less humic substances, so adding a few more is probabaly a good idea. Not too many at once to prevent oxygen depletion.

I can definitely reduce water changes if I ever need an uber acidic tank again

Wrong way round. Keep the waterchanges up, add more humic substances instead. Water quality before water parameters.

 

Hi again everyone! Sunday night I set some baby brine shrimp going...I had no heater on this hatchery, so there was not a useful amount of brine shrimp until this morning (Tuesday). The hatchery was a normal 1.25 liter bottle with two holes in the top (one for the air line, one for ventilation)...that design quickly proved to be a mistake, as harvesting the brine shrimp from such a setup was infuriating. With that being said, the baby bettas, the adults, and my sole surviving persian killifish (in my 10 gallon planted tank) were all thrilled with the brine shrimp...going to be starting more this evening (to harvest Thursday morning) in a more conventional, less irritating hatchery (an inverted bottle, basically). On the plus side, I discovered that using an air stone to aerate the hatchery works far better than using a normal air line...unless it proves overkill in the inverted bottle hatchery I am probably going to use an air stone from here on out (and am definitely going to do so if I ever try to use decapsulated brine shrimp eggs again).

 

Hi everyone! This morning I counted 6 fry in this tank...I do not know if that is all of them or whether there are more that have not come out of hiding (at least not when I tried to count them). In any event, I am happy there are not a huge number of fry in view of some of my prior mishaps with fish breeding (*cough* banded bushfish *cough*) and that the fry I do have are the fittest of the bunch (seeing how they managed to avoid their parents this long). I fed them baby brine shrimp this morning (I also fed some of it to the parents), and I picked up a tiny 5 watt heater at a local Petco today to heat the hatchery and get the brine shrimp to hatch within 24 hours, as well as a small kritter keeper-esque container to place the hatchery and the heater in (I may use that same container to grow out some of the brine shrimp I hatch).

 

Hi everyone! Two updates today...number 1, the fry count is up to seven

Number 2, I got two small microworm cultures in the mail today. Hopefully I will be able to get them established and have a secondary live food source for these fry and any other fry or small fish I may keep in the future.

 

Hi everyone...not a great update today. I found one of the males dead in the QT tank. The other three bettas are fine and well and water parameters (TDS, PH, ammonia, nitrite, nitrate) all checked out good, so I think he may have died of natural causes (this male was noticeably sickly to begin with). Currently preparing water change water for a water change just in case.

In more positive news, the microworm cultures have established themselves and are growing rapidly, so by early next week I should be able to supplement the fry's diet with microworms.