central American / Mexican tank… blind cave tetra question…

[Magnum Man]

so my sword fish from this area are going well, as are my dwarf Mexican cray fish… the sail fin mollys not so much… I’ve been reading up on central American fish, and while my fancy platy is line bred, seems platy’s in general are from the same area, so I’ll continue to add a few more wild types, and keep pretty boy in there, as he’s doing well in these tanks… the 45 gallon was full of larger caves for Tilapia breeding, that I did originally in these tanks… the caves got me thinking about the blind cave tetras… I see that they are all farmed now, and listed as a neutral ph water fish… I would think if these were truely cave fish, there would have been a pretty high mineral content in the cave water… is anyone familiar with these fish??? am I correct in thinking they were originally found in hard water, but were tolerant of softer water, and are now bred in more neutral waters… I’m wondering if I could add a small school to a harder water tank???

 

[Magnum Man]

this is one sellers information, on the fish…
“Blind Cave Tetra (Astyanax mexicanus), also known as the Mexican Cave Tetra, is an oddball tetra species. These fish are troglomorphic, meaning they are adapted to live in a lightless environment, and are fully missing their eyes! While they are adapted for a dark environment, these fish will still thrive in a standard aquarium setup and will generally do well with similarly sized tankmates.
Blind Cave Tetra (Astyanax mexicanus)

Origin: Tank Raised Asia
Diet: Micropredator and scavenger. Will accept most prepared and frozen foods in the aquarium
Adult Size: 3.5″
Recommended Tank Size: 20 gallons+
Compatibility: Peaceful towards any comparably sized tankmates

Preferred Water Parameters
pH: 6.0 – 7.2
Temp: 76-82F
Ammonia: 0ppm
Nitrite: 0ppm
Nitrate: <30ppm

I had these as a kid, but not in the last 50 years, so they have been in the hobby for a long time, and may not handle the hard water any more ( I lived in the same area 50 years ago, and the water was just as hard back then, though I knew a lot less than I do today )

… some texts go higher on the ph, so… maybe???

 

[GaryE]

I've been bitten by the eyed version (they were feeding off dry skin and it didn't hurt to be exfoliated by them) and they were in sunlit waters with X helleri swordtails present. In a big river, that was fine. In a fishtank, they can be nippy fish. The water needs are good with swordtails.
The marks on rocks showed a difference of easily six feet in water levels between rainy season, and dry season when I was there. So the dilution of water hardness from torrents of rain is part of their world. Fish like that adjust well to different waters.

Check full adult size. They'll get there, and it may be more than you're ready to deal with.

 

[BizzyBee]

Characteristics
This is a cave-dwelling form of the common tetra that has evolutionarily lost its eyes
It navigates using its lateral line and sensitivity to vibrations
Color: pale pink/white, sometimes slightly translucent

 

[Back in the fold]

Another old timer that I’ve never seen in person . Where do you find these rarities ?

 

[Magnum Man]

water change and substrate vacuum today on the rio tank, I have baby orange dwarf crays in this tank , as well as baby swords… this is one of the biggest dwarf crays, surveying his world…

 

[GaryE]

These used to be regulars in most decent sized pet stores - even in Walmart type pet departments here. I had them in my teens, and thought they were weird and cool. But as was the case with many fish when I was in my teens, they didn't get the long lifespans or size they should have.

 

[Magnum Man]

the cave tetras would go in the top tank, that has been struggling with the sail fin mollys, this tank also has been struggling with the other larger type swords there are still a few of both in that tank, along with an adult pair of super red bushy noses, a couple Florida flag fish both of these types are thriving in this tank, and I have the flag fish mating in my 5 gallon nano tank in a corner window, that is full of algae…
I’m done buying sail fins, I’ve killed too many of them… I may buy a few more wild type large swords, but the tank is pretty empty, so maybe see how the cave tetras do???

 

[Magnum Man]

@Back in the fold … only a few on line sellers have any in stock right now, but just about everyone worth their salt, has a listing for them…