Cyprinodon alvarezi---who knows anything about it?

[TyroneGenade]

Well, the subject line says it all. Anyone with experiance to share?

Thanks

Tyrone

[whuntley]

What do you want to know?

It is a pupfish from Mexico, that is now extinct in the wild. They are being preserved by hobbyists, but unfortunately-written laws makes criminals out of anyone who tries to save them, here.

Fortunately, it is still legal to keep species declared endangered or threatened in their home countries in most of Europe, so we have relied on them. I believe every single "extinct" pupfish species from Mexico is alive and well in a German or Scandanavian tank, somewhere.

Wright

[TyroneGenade]

I'm looking for info regarding keeping them alive in a fishtank.

Useful info would be:
1) what size tank (minimum)
2) foods and feeding
3) I understand they can chill quite happily at 5°C and feel cosy at 35°C.
4) size in aquarium.
5) breeding preferences: bottom/top mops, plants, incubation...
6) water quality: salty, fresh, alkaline, neutral, acid, pink, green...

Any thing useful you can think of.

Thanks

[whuntley]

1) what size tank (minimum)

10G might work, but 20 or larger is far better. They are social fish and need a gang, but males need a territory to defend. Pupfish do better in large tanks, even Cypr. diabolis. I prefer a 55G for any pupfish.

2) foods and feeding

All live foods, but greens are essential. They need algae or veggie supplements to do at all well.

3) I understand they can chill quite happily at 5°C and feel cosy at 35°C.

I don't think so. That would be the range of several different species, or maybe Cypr. radiosus which takes the widest known temperature range of any pupfish. Stick to 23-26C if you want to breed them, I think.

4) size in aquarium.

1.5" maybe?

5) breeding preferences: bottom/top mops, plants, incubation...

A fist-sized wad of filter floss on the bottom is best. One male will "own" each wad, so don't have them too close together. Bottom mops work, but egg predation is worse by non-spawning females.

6) water quality: salty, fresh, alkaline, neutral, acid, pink, green...

A bit hard with a touch of added salt would be OK. They are pretty tolerant of a wide range, AFAIK. Keep it very clean. They don't tolerate nitrite or ammonia well, but they are really pretty tough little fishes.

Wright