"Rio Orinoco Biotope" (20 Gallon long) advice.

[Aquaticloch]

Hello everyone,
I am doing a project for my school that is going to be a Biotope aquarium, particularly the Columbian section of this river.
I will be using a dense layer of leaf litter and alder cones to help get my water parameters down to blackwater conditions, if anyone has photos of this river or any tributaries that are close in proximity that would be much appreciated. I am trying to replicate it as accurately as possible without using materials solely found in the Amazon. I plan on mixing rainwater with tap or RO with tap at 70%, RO or rainwater to 30% tap. I'm hoping this will get my ph to 5.5 or below which is my goal.

My planned stocking list is as follows:
- 6 corydoras loxozonus
- 2 dicrossus filamentosus
- 4 nannostomus eques
This will be a community tank not a breeding tank.

Thanks for any insight and photos, Lochlan

 

[MacZ]

I have several comments:

The water: I also only use leaf litter and alder cones... And 95% RO. Actually 99%, I only add a liter of tap about once every 3 weeks or so. As long as you have readings for KH, botanicals will not move your pH further than to 6.5, maybe closer to 6 after some months. Just with adding a liter of alder cone extract each (weekly, pure RO) waterchange and a leaf litter bed, it took me a YEAR to get my pH down to 5.5.
For Rio Orinoco (which my N. eques species tank is basically) 5.5 is a good level, doesn't have to go below.

The fish:
Corydoras and a leaf litter bed equals clogged filters. Cories are sandbottom fish, that dwell in the middle zones of a creek where there is no leaf litter but some current. I would only keep the Dicrossus as bottomdwellers and stock up the Pencils to far more than 4. Instead of the cories rather think about midwater fish, maybe cardinals or the like. Or, after several months to build up biofilms, some Otocinclus. Maybe look into Otothyropsis, pricier, but much hardier than actual Otocinclus. (I know, not from the Orinoco, but Stand-ins are always an option imo)

I keep 15 N. eques in a 85l with lowered water line as a species tank and it's necessary to have quite a group size. The males are territorial, and as you will almost always get a surplus of males, the more the better as aggression disperses. Make sure there is enough structure (twigs, branches, floating plants) otherwise the pencils will likely start to decimate each other over time. Low ranking fish tend to be kept from eating and thus might starve. I avoid this by feeding lots of live artemia nauplii several times a week. Keeps them in shape.

 

[Aquaticloch]

Thank you very much for the reply macZ,
If i used a small amount of peat moss in the water before each waterchange would that help bring the ph down more quickly? Or is this method not very useful, as i know it has certain downsides.
Thanks again!

 

[MacZ]

Just to clarify: Peat moss is still green, living moss of the genus Sphagnum. In the early stages of decomposition it can also be called that. But what you need for water parameters is actual peat. The brown stuff you sometimes get as pellets (e.g. by Eheim or Fluval). It would be ideal to take a mesh bag of peat and either hang it in a back corner or put it in the filter if there is still room. Maybe a lump the size of a fist would be enough.
When you use straight up RO a bag can last you a month, maybe two before you have to replace it.

The downside of peat is first and foremost the fact it's not sustainable and helps destroying peat bogs that store a lot of CO2. The second downside is, that it can cause an oxygen depletion. Thirdly it can be a mess to handle.

But it would change the pH overnight.

For pretreating you could use a socalled "peat cannon". It's a pipe you fill densly with peat, you position it on top of your RO storage container and then you let the RO water run through the cannon into the container. A bit like brewing coffee. After that you press out the water from it like in a french press. Then you can either use it directly (which in most cases should be a bit too low pH) or dilute it with RO to where you want it.

If you want to keep it casual and the tank more of a community, combine botanicals (for stability) and peat in a bag (for pH).

Also experiment a bit with preparations and RO water in advance. See whether alder cone extract might be enough for what you want first, then try peat and see what rough ratios you would need.

 

[Jon Webb]

Just to clarify: Peat moss is still green, living moss of the genus Sphagnum. In the early stages of decomposition it can also be called that. But what you need for water parameters is actual peat. The brown stuff you sometimes get as pellets (e.g. by Eheim or Fluval). It would be ideal to take a mesh bag of peat and either hang it in a back corner or put it in the filter if there is still room. Maybe a lump the size of a fist would be enough.
When you use straight up RO a bag can last you a month, maybe two before you have to replace it.

The downside of peat is first and foremost the fact it's not sustainable and helps destroying peat bogs that store a lot of CO2. The second downside is, that it can cause an oxygen depletion. Thirdly it can be a mess to handle.

But it would change the pH overnight.

For pretreating you could use a socalled "peat cannon". It's a pipe you fill densly with peat, you position it on top of your RO storage container and then you let the RO water run through the cannon into the container. A bit like brewing coffee. After that you press out the water from it like in a french press. Then you can either use it directly (which in most cases should be a bit too low pH) or dilute it with RO to where you want it.

If you want to keep it casual and the tank more of a community, combine botanicals (for stability) and peat in a bag (for pH).

Also experiment a bit with preparations and RO water in advance. See whether alder cone extract might be enough for what you want first, then try peat and see what rough ratios you would need.

I agree with MacZ. Excellent summary re: peat. Oh, how I wish it was sustainable.

 

[shangman]

I keep 15 N. eques in a 85l with lowered water line as a species tank and it's necessary to have quite a group size. The males are territorial, and as you will almost always get a surplus of males, the more the better as aggression disperses. Make sure there is enough structure (twigs, branches, floating plants) otherwise the pencils will likely start to decimate each other over time. Low ranking fish tend to be kept from eating and thus might starve. I avoid this by feeding lots of live artemia nauplii several times a week. Keeps them in shape.

May I ask how low is your waterline from the top?

I have always wanted to keep the beautiful N. eques but as they are big jumpers and as all my tanks have emergent growth I can't fit a lid. Lowering the waterline could be a possibility though!

 

[MacZ]

May I ask how low is your waterline from the top?

I have always wanted to keep the beautiful N. eques but as they are big jumpers and as all my tanks have emergent growth I can't fit a lid. Lowering the waterline could be a possibility though!

Funnily enough they proved to be only panic-jumpers in my tank and that means I only see that happening e.g. when I do a little more than just the regular maintenance and unintentionally corral them into a corner. And even then it's not really actual jumping.

My tank is 45cm tall, usually the waterline would be at about 40-43cm, I lowered it to about 33-35cm.

 

[shangman]

Funnily enough they proved to be only panic-jumpers in my tank and that means I only see that happening e.g. when I do a little more than just the regular maintenance and unintentionally corral them into a corner. And even then it's not really actual jumping.

My tank is 45cm tall, usually the waterline would be at about 40-43cm, I lowered it to about 33-35cm.

Ahh that's very interesting about the panic jumping, it seems like at the angle they swim they're prime for going straight into the air at any time. Thanks very much for the waterline height, I'm going to see how the tank would look like that.. think it could be a winner!

 

[MacZ]

The angle is in my experience due to feeding habits as a picking browser and for camouflage. Between twigs and branches I often can't see them at first glance. Count them in this picture for example. There are 7 in it.

 

[Jon Webb]

Well, you got me. I only found one.

 

[MacZ]

Here's the answer.

 

[Jon Webb]

Well, you got me. I only found one.

Found more by checking the angles.

 

[rasmusW]

Well, you got me. I only found one.

Haha.. damn, hard to spot. I got 6

Ahh! And now i saw the answer too.
Oh! Well, fun quiz..

-r

 

[Aquaticloch]

Long Overdue update, the tank persists, still blackwater tank now on the third generation of iniridae in the aquarium, rasing themselves with the occasional mosquito larvae feeding! I never added anything else, just a pair to begin with. The initial grade 10 school project devolved into so much more!

The pH was extremely low for a time, think low fives, maybe even upper fours. wasnt able to read accurately due to lack of a meter and the amount of tannins. This got so low due to my tap water having a hardness of 28 straight from the pipes, and mixing with rain water when possible. Attached are a few photos along the timeline until now. I always like seeing progress, so wanted to share!

November 2021-

March 2022-

July 2022-

Today- Currently a grow out tank, fewer tannins so I can remove aggressors, but still acidic with leaf litter and floating plants. Plus a root system from the epiprenum aureum. Growing out 6 males and 1 female, think this is due to high temperatures.

 

[rasmusW]

Looked good.
Do you have any new plans for it or will you keep it as a grow out tank?

-r

 

[Aquaticloch]

I’ll return it to a biotope. In progress of selling the fish, save for one pair and move them to another tank. They are old now, and breeding on their own.

I’ll return it to the black water state when I can, considering adding some pencils and my single velifera male.

 

[anewbie]

While not directly related i wanted to share a bit of a story on aggression:
I had a 4 year old nijjensi female in my 40b and she liked to hang out under the very large crypt leaves near the front where i fed the fishes. I picked up a pair of D50 and figured the 40b was large enough for the 3 of them esp since the female nijjensi was solo and not a pair. After the D50 fully matured the male D50 started fighting with the female nijjensi and chased her off and when i noticed her i removed her to a 29 gallon aquarium (tall 20 long) that had some sparkling gourami and a solo female nannacara. The female nannacara objected tot he nijjensi and they started fighting - since I just moved the nijjensi i caught the female nannacara and put her in another 29 gallon that has some cardinals a runt angel and a single male agassiz that stared but didn't actually attack so for now i left her in that aquarium and will see how it goes. Anyway i guess the amount of area a fish requires can be quite large (in this case the solo female nannacara wanted the entire 29 and the d50 most of the 40) and both females and males are territorial even if there is no potential mate.