Can I make blackwater using my tap water?

[dw1305]

Hi all,

..... Hanna 98129, which is certainly not cheap at $200, but cheaper than what Darrel is suggesting.

If I was going to get a "cheap" pH meter, I'd get a Hanna one.

I believe it has a glass electrode as opposed to ISFET. It has a cap where you can put a few drops of buffer to keep the electrode wet. However, the cap is not airtight, and if you leave it for more than a few days it will definitely dry out. You can get around this by storing the unit upright in a beaker with some buffer at the bottom, sealing the top of the beaker with saran wrap or parafilm, like they do with more expensive probes.

That is one of the issues, the electrodes needed to be stored in 3 mol. KCl. The other problem is just that they work via ion exchange and the internal reservoir of potassium ions will eventually be exhausted requiring a new electrode.

I didn't calibrate mine every time (like you should for proper research). Instead, I would test it against a standard that's close to my target pH. If it was accurate, I didn't recalibrate. Still, this is all added effort, and you do need to periodically buy the standards and cleaning solution. I quite like not having to worry about pH anymore.

There are ongoing costs involved, with conductivity meters you can make up the calibration solution fairly easily, but it is more problematic for pH buffers.

Citric acid would work, but I think strong acids are simpler to use because they don't degrade.

You can get citric acid as a dry powder in the UK, not sure about elsewhere.

The problem with these extracts is that humic and fulvic acids aren't very soluble in water at acidic pH. If they're present in any appreciable concentration, they need to have a strong base added (often NaOH) to remain in solution. The resulting solution will be neutral to alkaline, which isn't the effect you're looking for.

I don't see any advantage to "blackwater extracts" either.

Cheers Darrel

 

[ButtNekkid]

The problem with these extracts is that humic and fulvic acids aren't very soluble in water at acidic pH. If they're present in any appreciable concentration, they need to have a strong base added (often NaOH) to remain in solution. The resulting solution will be neutral to alkaline, which isn't the effect you're looking for.

Hi,

Does this also account for the colouring effect of the extracts? I´m using JBL´s Tropol and it seems to go away in a couple of days.

 

[MacZ]

The colour goes lighter with pH going down. Just like black tea goes really light when you add lemon juice.

 

[anewbie]

Generically is ph relevant or are we just using ph as an indicator of kh exhaustion?

 

[MacZ]

or are we just using ph as an indicator of kh exhaustion?

Exactly. pH itself is secondary.

 

[Stijn1191]

Sorry for the hijack, but it does also fit with you cyano bacteria problem with leaf litter.

I also have some cyano bacteria problems in my blackwater aquarium, mainly in the leaf litter (where some 'liquid CO2" helps against if i spray on it with a syringe) and in the floating plants. Anyone else have this problem and know some easy/good fixes? 100% RO water here no NO3 and PO4.

 

[MacZ]

Sorry for the hijack, but it does also fit with you cyano bacteria problem with leaf litter.

I also have some cyano bacteria problems in my blackwater aquarium, mainly in the leaf litter (where some 'liquid CO2" helps against if i spray on it with a syringe) and in the floating plants. Anyone else have this problem and know some easy/good fixes? 100% RO water here no NO3 and PO4.

Asked the Mod-Team to move your post to a separate thread. This Thread here is still active, so a hijack is not an option.

 

[dw1305]

Hi all,

The colour goes lighter with pH going down. Just like black tea goes really light when you add lemon juice.

That makes sense <"https://www.mcgill.ca/oss/article/d...e-drinking-tea-you-are-also-drinking-some-ink">.

the iron-polyphenol complex is not stable in acid

Does this also account for the colouring effect of the extracts?

I think they are photodegraded as well <"https://www.sciencedirect.com/science/article/pii/S0926669021011687">.

cheers Darrel

 

[MacZ]

About store-bought extracts and colour: Cheap DIY alternative is organic rooibos tea without additives combined with alder cones.

 

[Ben Rhau]

Generically is ph relevant or are we just using ph as an indicator of kh exhaustion?

Maybe it depends? I know there are studies that say that pH can partially determine M/F ratio of offspring, so it may not be completely irrelevant.

At least in Parosphromenus species, nearly all serious breeders only keep them in water with virtually no KH/conductivity. Still, there are some species that empirically have only been successfully bred at pH or 2 or 3. Others breed completely fine at pH 5.5.

When I kept A. cf resticulosa, they would not breed at pH 7.8, but did breed quite immediately when I used a peat cannon and lowered the pH to around 6. Whether this had to do with the pH itself or other factors I can't reliably say.

I don't know of any controlled experiments to isolate the effect of pH.

Cheers

 

[Ben Rhau]

Hi,

Does this also account for the colouring effect of the extracts? I´m using JBL´s Tropol and it seems to go away in a couple of days.

Hm, maybe not for the same reasons... It sounds like you're asking whether the compounds that cause the coloring effect precipitate out of solution at acidic pH. If we're talking about humic and fulvic acids, we know that they're soluble enough to stain acidic blackwater so darkly that you almost can't see through it. But even that water is orders of magnitude less concentrated than what would be required in an extract/bottle.

But also, when you have a natural source of tannins, it's different than adding an extract as a one-time dose. For example, alder cones will continue tannins releasing at some rate until it's exhausted, and they're also being degraded at some other rate.

 

[Mazan]

This Thread here is still active, so a hijack is not an option.

Although actually this is interesting to me as I have experienced this issue, if I let a lot of leaf litter build up over a long time I seem to get cyanobacteria, especially in the roots of the floating plants and on the leaves themselves . Anyway yes, this does probably merit a new thread!

About store-bought extracts and colour: Cheap DIY alternative is organic rooibos tea without additives combined with alder cones.

I just wonder as they claim to have all sorts of things that are good for fish eg:
Dymax "The Black " claims
"Contains natural leaves extract that create a more natural environment similar to part of the Amazon River.
Contain necessary trace elements, vitamins and minerals that can help Arowana, Stingrays, Angel, Discus, Catfish, Plecos and other soft water fish to significantly reduce stress, promote spawning, enhance body colour, increase appetite, increase immunity and increase adaptability to new environments".

The same brand (which is new here) also has another called Ultra black - not sure what the difference is...

Azoo Triple black water claims similar "AZOO PLUS Triple Black Water replicates the natural habitat of Amazon black water, making it ideal for discus, South American cichlids, and other fish who thrive in acidic water. The improved formula is three times more concentrated than before and contains natural extracts including: humic acids, tannin, trace elements, vitamins, acids, fulvic acids, peat and almond leaves."

But if these compounds do not dissolve well in acidic water they may be useless or defeat the object??

And does Rooibos tea actually contain anything beneficial or is it used just for colour? I can't actually get it here but could potentially get someone to bring some from the UK....

Generically is ph relevant or are we just using ph as an indicator of kh exhaustion?

But what if there is virtually no kH anyway, but pH is considerably higher than that of blackwater??

Sorry for all the questions, I would just like to do things as well as possible, and it may not work in the end to breed the pike cichlids - I mean most cichlids "I have bred" - wrong phrase as they do the breeding! I have not had to do anything special to encourage them, but these pike cichlids are different. In any case it might not be possible - perhaps they are already too old, I read somewhere that in nature they probably mature very early and and live only one season. But I might as well have a go... I do appreciate all the information as well as in the other threads that have been linked, which I have been reading - some of which I had read before but not really with a view to doing anything about it. I don't want to use strong acids, I would be too nervous about getting it wrong and keeping everything stable. I will probably try peat if I can find some that is definitely pure, I am aware that it is not ecologically ethical which is a shame, but it does seem the best option for me I think, as just leaves (if I can find good tannin producing ones) it will take ages and ages for the pH to change.

 

[MacZ]

Dymax "The Black " claims

Directions say snake oil:

Directions:
Add 10ml (1 capful) of solution to every 60L of water. Water will not turn blackish colour after applying. Dissolve with some water before adding directly into the aquarium. Suitable for all freshwater aquarium. Use weakly after every water change. Shake well before use.

Azoo Triple black water

Dosage: Shake well before use and add to the aquarium water at the filter outlet. Add 10mL per 100 liters of water weekly or after a water change. One full cap is 20 mL; the inner cap is equal to 5 mL.

I wish I had a rofl emoji right now.

Yeah, well... do I really have to comment on that?

And does Rooibos tea actually contain anything beneficial or is it used just for colour? I can't actually get it here but could potentially get someone to bring some from the UK....

Mainly for colour, the stuff has antibacterial properties, but not woth it, you have better or at least equally useful stuff at hand locally.

 

[Mazan]

Directions say snake oil:




I wish I had a rofl emoji right now.

Yeah, well... do I really have to comment on that?

Haha I kind of thought as much!

 

[ButtNekkid]

Hi,

Thank you for all the great replys. Seems like Alder cones would be the way to go if one likes to get this sort of steady level of tint over longer periods?

@MacZ I tried your rooibos tea trick and loved the color! Just wished it would last longer.

 

[MacZ]

@MacZ I tried your rooibos tea trick and loved the color! Just wished it would last longer.

Means your pH is low. I usually do 3-4 bags per 2 Liters, works for 2-3 weeks.

 

[Stijn1191]

Asked the Mod-Team to move your post to a separate thread. This Thread here is still active, so a hijack is not an option.

I'll make my own seperate thread, thank you.

 

[dw1305]

Hi all

When I kept A. cf resticulosa, they would not breed at pH 7.8, but did breed quite immediately when I used a peat cannon and lowered the pH to around 6. Whether this had to do with the pH itself or other factors I can't reliably say.

Peat would have some caution exchange capacity, (it would swap an internal H+ for a Ca++ etc. in the water column).

Cheers Darrel

 

[Ben Rhau]

Hi all

Peat would have some caution exchange capacity, (it would swap an internal H+ for a Ca++ etc. in the water column).

Cheers Darrel

Yes, I will add that conductivity did not appreciably change, though I suppose it’s possible that GH makes a difference. There were also dissolved organics released to the water.

 

[dw1305]

Hi all,

I will add that conductivity did not appreciably change

You've swapped a proton and I think that the proton (H+) would be a slightly less conductive than ions with a higher valency, like calcium (Ca++), and you swapped them 1 : 1.

I think size is also important (smaller = more conductivity), and you can't get any smaller than a H+ ion, so I'm guessing they balance out, but you need a <"real scientist at this point">.

The added protons would lower pH, because one definition of an acid is a <"proton donor">.

cheers Darrel