Central America black water

[Tripping Willow 91]

I've just set up my first cichlid tank, it will be home to a group of meeki and swordtails. I'm using lots of botanicals, leaf litter and wood in the tank and of course this means lots of tannins, which is fine with me as I've always fancied a black water tank and I love the stained water look.

It might be a stupid question but what I'd like to know is do central american cichlids specifically T. meeki naturally inhabit black water type rivers and pools, does central american have black water rivers? I've found plenty of videos of meeki in waters where the bottom is covered in leaf litter, wood, algae and mud but considering this the water always looks surprisingly clear. Perhaps it's the camera making it look clearer than it is but living in sunny old England and having never left Europe I have no personal experience to go on

 

[ryansmith83]

No, there are no major blackwater systems in CA.

 

[Tripping Willow 91]

No, there are no major blackwater systems in CA.

Thanks, you learn something new everyday

 

[duanes]

Agree
In much of Central America, the water is caicum/mineral rich, pH 7.5 and above (up to pH 9 in some place)s, which tend to neutralize the tannic acids quickly, those that create black water.
T. meeki is generally found in pH 7.5 and above clear, or turbid water habitat.

Amazonian South American waters are generally and considerably mineral poor which allows the tannins to remain in solution.
These tannins can in large amounts lower pH into th 4-6 range.

Here in Panama (and elsewhere in C America) there are black water areas, like placid pools, swamps, and jungle streams that contain black water.
Being mostly shallow (only inches deep), these are not normally cichlid habitat. Species like killifish, mosquito fish, and other smaller species make use of them.
The black water won't hurt your Thorichthys, as long as pH remains stable

 

[Tripping Willow 91]

Agree
In much of Central America, the water is caicum/mineral rich, pH 7.5 and above (up to pH 9 in some place)s, which tend to neutralize the tannic acids quickly, those that create black water.
T. meeki is generally found in pH 7.5 and above clear, or turbid water habitat.

Amazonian South American waters are generally and considerably mineral poor which allows the tannins to remain in solution.
These tannins can in large amounts lower pH into th 4-6 range.

Here in Panama (and elsewhere in C America) there are black water areas, like placid pools, swamps, and jungle streams that contain black water.
Being mostly shallow (only inches deep), these are not normally cichlid habitat. Species like killifish, mosquito fish, and other smaller species make use of them.
The black water won't hurt your Thorichthys, as long as pH remains stable

Thank you, I believe that answers the second question I was going to ask. I knew hard water buffered out the pH lowering effects of tannins but I was unaware it would actually remove/neutralise the stain from the water, is that correct? This would explain why my tank is looking a lot clearer just 1day after filling it with tannin filled boiled water from alder cones and oak leaves, my water is 8ph, 20gh and 10kh

 

[duanes]

As an experiment, I began adding almond leaves regularly to my 300 gal system.
My water has a pH of 8.0 to 8.2 with 180m/L carbonate hardness, and around 200 m/L . general hardness.
The link below.

Experiment w Almond Leaves

There are at least 2 almond trees on the island where I live, and after todays 4 hour storm, I collected about a half dozen fallen leaves . These were dropped in my tank (180 gal with a nearly full 125 gal sump) still floating a couple hours later Initial pH was measured 3 times with 3 aliquots...

www.monsterfishkeepers.com

I could not with all the leaf litter I added, get pH to drop even a tenth, or get a slight color tint.
I believe the combination of hardness, immediately neutralized all tannic acids as they were released from the leaves.

 

[Midwater]

I could not with all the leaf litter I added, get pH to drop even a tenth, or get a slight color tint.
I believe the combination of hardness, immediately neutralized all tannic acids as they were released from the leaves.

I have noticed that too. I weekly change a net bag full of about thirty of forty indian almond leaves directly in the sump, and the PH remains 7.5, same as tap water.

I did boil up a few leaves in a pan of water, and that barely got the PH down to 7.2.

 

[Tripping Willow 91]

As an experiment, I began adding almond leaves regularly to my 300 gal system.
My water has a pH of 8.0 to 8.2 with 180m/L carbonate hardness, and around 200 m/L . general hardness.
The link below.

Experiment w Almond Leaves

There are at least 2 almond trees on the island where I live, and after todays 4 hour storm, I collected about a half dozen fallen leaves . These were dropped in my tank (180 gal with a nearly full 125 gal sump) still floating a couple hours later Initial pH was measured 3 times with 3 aliquots...

www.monsterfishkeepers.com

I could not with all the leaf litter I added, get pH to drop even a tenth, or get a slight color tint.
I believe the combination of hardness, immediately neutralized all tannic acids as they were released from the leaves.

Your almond leaf experiment backs up what I've read about tannins having little to no effect on the pH of very hard water and is easily buffered. I added a considerable amount of tannin tea in one go, this is the first time I've used botanicals and I wasn't expecting so much colour to be released from them. I used around 25 alder cones and a dozen oak leaves boiled in approximately 2l of water for 30mins, cooled and then everything (cones and leaves included) poured into the tank. This added a considerable tint to the water (the tank is 240litres/63us gal) and made it difficult to even see the heaters on the rear glass, the tank is only 40cm deep. I didn't test my pH as I didn't expect that to alter and assumed my very hard water would remain stable, I will check this this evening though as I'm now curious. What surprised me is that my water has become a lot clearer after only one day, I was expecting it to become darker over the next few days as tannins will surely still be leaching from my botanicals. It seems my water is actually clearing away the tint somehow, unless it's my filters? Would sponge and lava rock reduce the tint? Where is the tint going?

Pic 1 is just after the tannins were added
Pic 2 is 31hours later

 

[Rocksor]

Your almond leaf experiment backs up what I've read about tannins having little to no effect on the pH of very hard water and is easily buffered. I added a considerable amount of tannin tea in one go, this is the first time I've used botanicals and I wasn't expecting so much colour to be released from them. I used around 25 alder cones and a dozen oak leaves boiled in approximately 2l of water for 30mins, cooled and then everything (cones and leaves included) poured into the tank. This added a considerable tint to the water (the tank is 240litres/63us gal) and made it difficult to even see the heaters on the rear glass, the tank is only 40cm deep. I didn't test my pH as I didn't expect that to alter and assumed my very hard water would remain stable, I will check this this evening though as I'm now curious. What surprised me is that my water has become a lot clearer after only one day, I was expecting it to become darker over the next few days as tannins will surely still be leaching from my botanicals. It seems my water is actually clearing away the tint somehow, unless it's my filters? Would sponge and lava rock reduce the tint? Where is the tint going?

Pic 1 is just after the tannins were added
Pic 2 is 31hours later

View attachment 1485472

View attachment 1485473

I've used laguna pond liquid peat, so it's super concentrated. I add about 2-3 tablespoons worth to 210g water. No effect on PH (KH is 8 degrees), but the brown tint will remain for a week before a water change and it does lighten by about 50% over the course of 24-48 hours. By the time I get to the bottom of the bottle of the liquid peat, there's a thick sludge that can be diluted when mixed with water. When I open my canister filters after 2-3 months, all the bacterial slime is coated in peat tint that will temporarily stain my fingers until washed. A majority of the peat extract "leftover" is in the canister head with the impeller and top coarse sponge.

So my guess is that some of the tint from peat is particulate matter

 

[duanes]

So my guess is that some of the tint from peat is particulate matter

Agree, and because tannins are organic they will decompose (albeit slowly) get neutralized by buffers, reused by plants, etc , so will need to be constantly replenished.
At the end of the dry season, the first heavy rains inundate my tanks with tannins, but once depleted from the surrounding foliage the tanks quickly go from brown to relatively clear.

above sump cover, below tank after the first seasonal rains.

a few weeks later they are gone
I have never used the Laguna product, but it seems perfect for Black Water tanks.