blackwater tank

[abaigael04]

How best to set one up? I have read all different ways - just adding some commercially available product, oak leaves, peat moss in the filter.
I think I will be adding some percentage of distilled water to my water to lower my hardness and ph (GH - about 9
Kh - 2-3 (it is hard to tell the colors EXACTLY) --- this is from my *tank*... If I should test my tap, I will.. - ph in my tanks is about 6.8 (with driftwood). I am looking to set up another 60 gallon blackwater tank. Also - my Ph test only goes to 6.0 - well I need my ph right around there, but need to know my tank is stable - but if it goes below 6.0 - I will have no way of knowing as my tests will always say 6.0 regardless - is there a ph test out there that tests from say 5.0??? Thanks!

[hotsauce48]

I got blackwater in my tank naturaly with driftwood.I soaked it for a day and put it in my tank.The water took a couple of days to get brown.There is another way to do this too.That is by buying some of tetras blackwater extract.
http://www.petsolutions.com/Images.aspx?ItemID=46716270

[abaigael04]

Driftwood isn't enough for me - I have lots of driftwood in my 125 gallon and my tank is nowhere near blackwater conditions. That is what I am asking - are those commercial products worth it? Does it stay stable? and for a Ph test that tests lower than 6?

[Haavard Stoere]

Large amounts of okleaf is very potent for both coloring the water and for lowering ph some. However your high gh and kh will make it difficult to get really low ph if that is what your aiming for.
Reverse osmosis water or rainwater will of course solve the hardness issue.

What species of fish to you intend to keep?

[abaigael04]

Yep - I have already decided on doing some RO/distilled/rain water in this tank - for the reasons you stated - so I just need to figure the rest out. Just wondering which method is best, most stable and how to test with a ph so low.. Where can you get oak leaves? I am hoping to keep a few L239 - in a tank dedicated to them.

[OldMan]

Well abaigael04, RO/DI is an expensive way to force yourself to buy minerals to put into the water. No fish, not even extreme blackwater fish, can live in demineralized water. If you get DI you will be adding minerals back in by either using a chemical blend like RO Right or by blending with tap water. A better alternative would be to go to RO only and not need to add back as much tap water or minerals to achieve the end result. This would not be the case if your water was inherently unsuitable for fish, but if it is only a little high in minerals, the DI is a waste of money every few months when the resin needs to be replaced as well as being more expensive to install.

[MatsP]

I'd also like to point out that Rio Orinoco that L239 comes from isn't a blackwater river as such - not in the same sense as for example Rio Negro.

Soft water, yes, but not really really soft.

Also, water that is so soft as you'd find in Rio Negro and other similar waters is almost impossible to maintain in a tank - that is because the tank is a closed system. A river flows lots of water over the fish, and anything that happens in one place will be move away shortly. In a closed system, any chemicals produced in the tank stay in place. So aiming to maintain an environment that resembles the natural pH, KH, GH values is bound to lead to bad things - pH crash being the most obvious result - and that can kill your fish. So my advice would be to maintain soft, but not overly soft water. My fish appear to be happy with a TDS value of 100 ppm, which consists of a mixture of calcium salts (mainly calcium sulfate - essentially GH) and bicarbonates (essentially pure KH) in about equal mix. That is perhaps a bit higher than you'd like to go, but I would definitely avoid theTDS of 8 ppm or some such that you'd find in the wild - it is unsustainable in practice in a tank.

--
Mats

[racoll]

I would also argue that the L239 do not need ultra-soft and acid water. They will, like most other loricariids be more than happy in the kind of medium-soft water Mats keeps his in (100mg/l). I wouldn't however go below 50mg/l, because this is when the pH dips to below 6, and crashes can occur. You can mix up the exact hardness/pH values with the commercial KH/GH salt mixes.

Loricariids are not as demanding as for example blackwater cichlids or anabantoids, and you are more likely to harm the plecos by trying to mimic their natural environment due to the unstable conditions of a tank with no buffering capacity.

and how to test with a ph so low

Get a quality digital meter, and calibrate it frequently.

[abaigael04]

Thank you all very much. I will look for a better way to test ph and I have been meaning to get a TDS meter, so now I will just have to get on it. Will have a goal to lower my Ph but not super low or anything, and will keep everything moderate. My water is fine for for - just a bit high in minerals.

[MatsP]

Yeah, Texas has fairly hard water in some places - at least around Austin and south thereof that I've visited has "water you can walk on" as someone else said.

--
Mats

[hotsauce48]

That tetra blackwater extract does not effect you're ph.And it also stays stable if you dose and restore it properly after chaning water.

[MatsP]

That tetra blackwater extract does not effect you're ph.And it also stays stable if you dose and restore it properly after chaning water.

I'm not sure. The blurb I can find on the Web doesn't appear to say. I would expect that if it has a large effect on the water, it woudl clearly state so.

Note also that if your water is hard, then it is VERY difficult to change the pH - you need to remove the hardness to lower the pH, and no "adding something to the water" can do that - you can, at best, replace it with something else by a "water softener", but then you haven't actually achieved what the fishes want, because it's replacing the hardness with salt, and now you have water that ever so slightly brackish. That's definitely not good for the fish, even if technically you have achieved soft water - but like painting black stripes on a horse and calling it a zebra.

--
Mats

[abaigael04]

but if I use RO water, that will get me where I want, no? I was going to do part RO/part tap and just mixing it for every water change... I don't think I am adding any 'extract' to the tank - am going to try and recreate the habitat semi-naturally (oak leaves, etc.).

Edit: I am SE of Austin... I will be moving to a different (close by) city BEFORE setting this tank up, so not 100% what exactly the water will be like. I also already have an L-239 who appears to be very happy. But I wanted a tank close to their natural habitat and to have it be dedicated to them. While my water is hard, it isn't VERY hard, either.

[MatsP]

South East of Austin - where abouts? If you still get water from LCRA, then this (10 year old) table may be of some help:
http://www.ci.austin.tx.us/water/watersummary.htm

This is also a good place to determine hardness.
http://water.usgs.gov/owq/hardness-alkalinity.html#1
It appears that the treated water is actually lower in hardness/TDS than the "raw" water, which is a bit surprising to me - must be that they mix it from differen sources.

You can also see that the tap-water is high in ammonia, which I take to indicate addition of Chloramine for antibacterial purposes, rather than using chlorine on it's own. pH in tap-water is also EXTREMELY high, probably at least in part due to the Chloramine - I'd check if a dechlorinator designed for chloramine reduces the pH - leaving the water to stand for some time will help.

Yes, a mix of RO and tap-water should be able to create the right conditions for you - just adjust the mix of water to suit the conditions you want.

--
Mats

[racoll]

but if I use RO water, that will get me where I want, no?

Yes, a mix of RO and tap-water should be able to create the right conditions for you - just adjust the mix of water to suit the conditions you want.

Yes, just mix it until you get a nice stable pH just below seven.

am going to try and recreate the habitat semi-naturally (oak leaves, etc.).

I would not include any kind of leaves in a tank set up for warm water rheophilic Ancistrini. There will probably not be leaves in the natural habitat, as the water will be running too fast.

Decomposing organic material (like leaves) in the tank will remove precious oxygen, and when keeping delicate, oxygen hungry fish like L239, I would concentrate of maximising oxygen, especially as these fish need to be kept warm, at 27-29C.

Treat this fish as you would a gold nugget (

Baryancistrus

) and you won't go far wrong.

In light of this, I would just decorate with river rocks, sand, and a few bogwood branches to lightly stain the water.

[abaigael04]

It just ate my post! At any rate- saw on another post these were blackwater fish, but am happy they are not true blackwater fish. I was already planning on wood, rocks & flow - so that is all good. No leaves.

I live south of Houston, tap ammonia is 1. Ph levels out to 6.8 in both of my tanks (one with driftwood, one without). Will check out those links. Will also lookup the Bary. This is my first time tailoring a tank to a fish and so just doing all my research so I know ! No point completely setting a tank up for a fish & have it be wrong! Thanks again!

[Bas Pels]

I would not include any kind of leaves in a tank set up for warm water rheophilic Ancistrini. There will probably not be leaves in the natural habitat, as the water will be running too fast.

Decomposing organic material (like leaves) in the tank will remove precious oxygen, and when keeping delicate, oxygen hungry fish like L239, I would concentrate of maximising oxygen, especially as these fish need to be kept warm, at 27-29C.

I think - my interpretation - Racoll basically wrote rheophilic fish don't life in blackwater. thinking about it, i think he is right (that is, if I may read him this way)

Black water is water which, after it rained down, did not take up many minerals, but it took up organic material, mostly decomposed plants.

Tropical rainforests all have a very humus rich soil, keeping rain away from the bedrock, and thus all prioduce blackwater

Rheophilic fish life in fast moving water (rheophil means loving fast moving water). This moving water rapidly remouves all soil and thus rheophilic fishes life on the bedrock

Fast moving water is something we expect to see in mountains, in any case, not only the river goes steeply down, but the surroundings too. In most areas, this means not a lot of soil is around

Therefore, where the water is moving fast, the conditions are far from ideal to produce black water

Thanks, Racoll, for this eye opener

[racoll]

Erm, not exactly what I meant Bas, but it is always good to stimulate the mind and ask yourself a few questions.

I simply meant that the immediate habitat where L239 would be collected (i.e. fast moving water over rocks) there would not be many dead leaves, as they would be washed away, and so would not be a good inclusion for the biotope aquarium.

There are many rapids on the blackwater Rio Negro, e.g. at São Gabriel da Cachoeira, which is where I believe

Ancistrus dolichopterus

is collected.

The mineral content of the water relates to the geological age/composition of the drainage basin.