Blackwater 5 gallon journal!

Overdue tank pic! Just took this a few minutes ago

 

Hmmm...the PH bounced back up to the high 5's by this morning I think I know what is happening, though...when dissolved in water, carbon dioxide partially converts into carbonates, with the exact ratio of the CO2 that does this depending on the PH of the water it is being dissolved into. In my tank, which normally has a PH of about 6, assuming a normal low tech CO2 concentration of about 3 ppm results in about .1 degrees KH in the water...that sounds very low, but when I did the math based off the respective molar masses of sulfuric acid (PH down's active ingredient) and carbonates the tank likely had more than ten times the amount of carbonates required to neutralize all the PH down I added yesterday. If I decide I still want the tank to have a low (4-5.5) PH, I will need to do more experimenting to identify how much acid is needed to get the PH to stably remain below 6...I may resort to trying to use sodium bisulfate instead of the PH down, as the former is cheaper than PH down and far safer than pure sulfuric acid.

EDIT: Oops! I accidentally calculated for 18 ppm carbonates (about 1 degree KH) instead of 1.8 ppm carbonates...1.8 ppm carbonates is still enough to neutralize all the acid I added yesterday, but not by as wide a margin. As carbonate production drops sharply with lower PH, maintaining a low PH will be markedly easier once I get the PH to stay low for the first time.

 

HI everyone! Did water change number 4 yesterday, and I (FINALLY!) got the PH to stay below 6 by adding more than enough PH down (a quarter teaspoon's worth) with the new water to neutralize all the carbonates the tank had acquired from gas exchange. As of this morning, the tank has a PH in the mid 4's and TDS of about 29 ppm...the latter is a bit higher than I intended, likely due to the large amount of PH down I used. Since the tank will now produce carbonates much more slowly due to its low PH, I will not need to add nearly as much PH down (or whatever acid I choose to use) next time to maintain its acidity.

Meanwhile, the round pellia, golden creeping jenny, and especially the Mayaca fluvitalis are growing quite well in this setup (the latter has grown several inches since being introduced to this tank! Clearly it outright enjoys soft, acidic water). The Rotala H'ra is also growing well and even developing a red tint in the new growth, but many of the stems have black portions on them, most likely due to me accidentally damaging the stem while I was trying to plant them...I may need to replant the tops at some point soon. I will post a picture of the tank tomorrow for consistency's sake.

 

Here is the promised tank picture! Took it this morning about 8:40 am EST...note the Mayaca in the black that has grown like mad (EDIT: Comparing this to the previous picture reveals the Mayaca has grown several inches in a week! This plant is nuts! :eek;




On another note...I think I have decided on a fish for this tank; Parosphromenus opallios - a licorice gourami that did not even have a good picture online until recently. I will most likely be getting a small group from Blackwater aquatics in January...the owner gave me permission to use a picture he has on his site of a male P. opallios;

 

HI everyone! Here's an update about my system...the tank is doing well, but I am having trouble setting up a DI resin filter. The previous design was resulting in water trickling through only a small part of the resin, rapidly exhausting the resin in its path and leaving the rest of the filter untouched. I attempted to build another design that deposited water at the bottom of the filter, forcing it to flow through the DI resin before draining out of a hole above the resin, but that filter flowed VERY slowly and attempting to get it to flow at a remotely reasonable rate caused the water to be forced back out the filter's intake...basically, this filter needs some serious work

In other news, the TDS of the tank itself fell to 24 ppm and the PH rose to about 5...maybe there were more carbonates in the water than I thought? Hopefully it does not climb any higher...

 

HI everyone! I had a brainstorm this afternoon and FINALLY devised a successful DI resin filter The best part is how simple it is! I made it using a cylindrical container, 1 1/2 cups DI resin, and an air pump. I add a full strength air line to the container that continually resuspends the resin in the water I add to the filter; I wait 2 minutes, remove the airline, then wait another 20 seconds to test the water. This filter turns 600 ml of roughly 37 ppm TDS water into 0-2 ppm water in that time...adding up to roughly one gallon every 17 minutes, a HUGE improvement over my prior filters. The filter would probably be even more efficient with a funnel shaped container like an old soda bottle, as with the current container not all of the DI resin is constantly in suspension (some of it settles on the bottom away from the airline).

EDIT: You will need to pour the filtered water through a brine shrimp net or other very fine mesh to keep DI resin particles from getting in your tank. It's a minor downside, but still worth mentioning.

 

HI everyone! Here's a tank update. Yesterday I did a water change on the tank because I thought I would not have time to do it today...parameters yesterday before the water change were 26 ppm TDS and a PH of 5.5. I removed two gallons of water and replaced it with water I purified with my new DI resin design, with 10 drops API PH down added. Parameters as of this morning are PH 5, TDS 18 ppm.

The plant layout has changed noticeably since the last picture. The mayaca fluvitalis had to be trimmed twice this week...once Wednesday, and once during the water change. About 2/3rds of the stems had to be trimmed to prevent them from breaking the water surface, and the cuttings were planted nearby (though they will likely be too short to be visible in Monday's tank picture). The Rotala H'ra is also growing decently and even turning reddish on the top, but many of the stems had been damaged when I first planted the tank and were rotting away, so I had to trim off the healthy tops of the damaged stems, replant them, and discard the rotten portions. The golden creeping jenny is both healthy and has not reached the water surface yet, so it was left largely untouched except for a single stem that I accidentally uprooted during the water change, which had to be replanted.

 

HI everyone! Here are the promised pictures First, here's a frontal view of the tank;


Next, here's a close up of the Rotala H'ra...note the orange color on top of the stem;


Here's a closeup of the unexpectedly weed-like Mayaca fluvitalis;


And finally, here is a side view of the tank;


Thanks for viewing!

 

HI everyone! Just a little update on my water purifying filter...I have built my most effective filter to date It's even simpler than the previous one - I put 2 cups of DI resin in a rinsed 1.25 liter soda bottle, then added 600-700 ml of the water I intended to filter. After this I screw the cap on the bottle and shake it vigorously for 30 seconds; after letting the resin settle for another 20 seconds, I pour the water through a brine shrimp net (to keep stray resin particles out of the purified water...I'd recommend using a net dedicated to that purpose rather than one actually used to harvest brine shrimp) and repeat the process. Each of these cycles produce 600 ml of purified water; at this rate I could produce a gallon of purified water in about 7 minutes - comparable to the rate of a 200 GPH reverse osmosis unit Plus, it's actually rather fun to shake the bottle A larger 2 liter bottle (with about 768 ml resin and up to 1200 ml water) could produce purified water even more quickly, at about 1 gallon in less than 4 minutes.

 

So this is what happens when someone with a background in chemistry does a blackwater tank. Lot of useful info, dude.

I'm max.surprised the bandarole is still on the bottle. And it somehow irritates me, when I look at the pictures. Ever thought of removing it?

 

The logo sticker? Yeah, I can remove it...I've just been lazy about it until now. I'll remove it by the end of today.

EDIT: Your wish has been granted Here are pictures I took of the tank shortly after the logo sticker was removed from the bottle filter;




My mom drinks a lot of diet coke, so it makes sense that I would have a variety of uses for the resultant empty soda bottles...

 

And suddenly it blends into the background. Looks really nice now. The logo was very out of place. Thank you so much!

 

And suddenly it blends into the background. Looks really nice now. The logo was very out of place. Thank you so much!

No prob I too am surprised how well it blends into the background now that the logo is gone.

 

I just realized, that it now finally looks like a blackwater tank. Before it looked like breeding for profit or something. Like improvised in the "at least it works"-way. But somehow I feel like a home tank also needs to be visually pleasing. And the filter now blending in really does this.

 

Good job op, tank looks good. Looking foward to updates.

 

HI everyone! The blackwater tank has hit a snag I found a damselfly larvae in the tank...a 1 inch long damselfly larvae It probably hitchhiked into the tank on the plants I purchased for it about a month ago. I promptly captured and killed it, but since it is likely that additional larvae exist this sets back adding fish to the tank until all the larvae have been killed. Bummer...

 

HI everyone...long time no post. This has been a bad week for the family...on 12/8/19 my grandfather was admitted to the hospital for heart failure, and he died yesterday. Needless to say, I have not been paying a lot of attention to my tanks in that time...so, here's a long overdue update;

The blackwater tank is doing OK. TDS is about 27 ppm currently; I have not tested the PH in a while. The mayaca fluvitalis is still growing like a weed, often requiring two trimmings a week; the other three plants are also growing well, though much more slowly (and the Rotala no longer has any red coloration for some reason). I am going to be doing a water change Saturday, as I missed last Saturday's water change due to my grandfather's declining health. Here is the tank as of a few minutes ago;




I have not seen any additional mayfly larvae and there are likely no others in the tank, but I will still be treating the tank with a Chitin synthesis inhibitor before adding any fish. Thanks for reading.

 

Sorry for your loss. Tank looks good despite neglect.

 

HI everyone! Here's an update...I finally got water changes on my tank done yesterday. To the gallon blackwater I added - along with the new water - a 120th of a teaspoon of sodium bisulfate. TDS as of this morning is 21 ppm and the PH is about 5. I also trimmed the Mayaca fluvitalis and the golden creeping jenny. I will post a picture later today.

 

HI everyone! Here is the (overdue ) tank shot;



I really am considering removing the Rotala...it is growing well, but I am no good at planting it in the (less than ideal) substrate without breaking the stem. On a side note...the tank is almost 2 months old now (my first dated picture of this tank was October 29th).

 

HI everyone! I did a water change on all my tanks last night. To the blackwater tank I added 2 gallons of purified water and a 60th of a teaspoon of sodium bisulfate, resulting in a TDS of 28 ppm (a tad higher than desired) and a PH of 5. This is only a slight improvement over last week, so I am not going to add this much bisulfate next week. I also removed the rotala and moved the round pellia to where it had been. Here is the tank pic...enjoy!

 

HI everyone! It's been a rough week-10 days, but I finally got a 40% WC done on the tank today, and while I will not have a picture ready until tomorrow here is a short update. The Mayaca fluvitalis is still growing like mad...I am about ready to give up on trimming it, as it seems to need trimming twice a week or more. The other plants are growing much more slowly but still doing well. I removed some of the older leaves from this tank and added some new leaves and two birch cones for tannin and microfauna production. I did not test the new water parameters, but will test and post them tomorrow.

 

HI everyone! Here is the promised tank picture;




The new leaves and birch cones have darkened the tank noticeably since the water change yesterday...anyhow, the TDS is about 25 ppm and the PH is about 5. Some green algae growth is visible on the glass, but it is quite soft and easily scraped off. Still no sign of additional damselfly larvae, but I will likely not be getting fish this month after all because I am still working on my Grandma's tank.

 

Looks awesome!

 

Looks awesome!

Thanks!

 

HI everyone! Here's another update Yesterday I did a 40% WC on all my tanks, including the blackwater; in the process, I extensively trimmed the Mayaca (producing about a dozen 4-6 inch stems!) and cleared out a spot in the front left corner for additional plants. As of this morning, TDS was about 20 ppm and PH in the low to mid 5's. Here is a picture I took this morning;

 

Low to mid 5s... Now the choice of possible fish is shrinking, isn't it?

 

Low to mid 5s... Now the choice of possible fish is shrinking, isn't it?

That's a perfect PH for the licorice gouramies and wild bettas I am considering...I previously bred Parosphromenus 'sentang' licorice gouramies in a 5 gallon tank whose PH was in the mid to high 4's. A larger (20 gallon plus) version of this tank could have dozens or perhaps even hundreds of stocking options from the Rio Negro or Southeast Asian peat swamp forests, among other places...its primary limit is its size.

 

And availability. That's what I was aiming for. I must admit, most of your choices of fish here is either not interesting to me or actually too unusual to have heard of them.

I'm mainly interested in south americans and especially tetras. I mean... those parameters and I'd consider breeding my cardinals. I've given up on the pH-chase. I'm fine with my 6.8 directly from tap and usually around 6.4-6.6 in the tank depending on the time of day.

 

And availability. That's what I was aiming for. I must admit, most of your choices of fish here is either not interesting to me or actually too unusual to have heard of them.

I'm mainly interested in south americans and especially tetras. I mean... those parameters and I'd consider breeding my cardinals. I've given up on the pH-chase. I'm fine with my 6.8 directly from tap and usually around 6.4-6.6 in the tank depending on the time of day.

I can understand that...the water is as soft as it is acidic (hardness is zero or very close). In spite of the lack of hardness, this tank has been surprisingly hard to push the PH down in...for a long time it was not dropping below the high 5's/low 6's stably.

 

No comparison to mine. Kh 6, gh 8. This is nice for slightly acidic but will not go below 6.2 without switching to ro water.

 

HI everyone! Overdue update. Here's a tank pic I took a few minutes ago;




Current parameters are PH in the low 5's and TDS in the low 20's ppm. I have started soaking 4 birch cones per gallon of the new water for several days before each water change (hence the darker color of the tank). I also got a red flame sword in the mail today...time will tell how it does.

 

HI everyone...here's an update. I tore the tank down...


Sounds rash, but let me explain. My interests have been shifting lately towards plant growing...currently houseplants, but I will also be experimenting with hydroponic vegetables and pond plants when warmer weather arrives. This shift in interests has made it more difficult for me to keep up with my tanks, especially this one (which is more labor intensive than my other tanks even considering it doesn't have fish yet). It also occurred to me that, even if I did succeed in keeping and breeding endangered licorice gouramies and/or wild bettas, could I ever save their wild habitats or return them to the wild if someone else did? Both would be a near-impossible task for a poor bloke living in New England who hates traveling .

I have no intention of giving up the hobby...I'm just changing my main focus and adjusting my setups accordingly. The now-empty 5 gallon may thus be reborn as a terrarium or an experimental 'hi-tech' planted shrimp tank (in practice it will use yeast for the CO2 if I go that route). I will keep you posted when I decide what to do with this tank. Thanks for viewing this thread

 

HI everyone...here's an update. I tore the tank down...


Sounds rash, but let me explain. My interests have been shifting lately towards plant growing...currently houseplants, but I will also be experimenting with hydroponic vegetables and pond plants when warmer weather arrives. This shift in interests has made it more difficult for me to keep up with my tanks, especially this one (which is more labor intensive than my other tanks even considering it doesn't have fish yet). It also occurred to me that, even if I did succeed in keeping and breeding endangered licorice gouramies and/or wild bettas, could I ever save their wild habitats or return them to the wild if someone else did? Both would be a near-impossible task for a poor bloke living in New England who hates traveling .

I have no intention of giving up the hobby...I'm just changing my main focus and adjusting my setups accordingly. The now-empty 5 gallon may thus be reborn as a terrarium or an experimental 'hi-tech' planted shrimp tank (in practice it will use yeast for the CO2 if I go that route). I will keep you posted when I decide what to do with this tank. Thanks for viewing this thread

Shame but I respect the decision