Stocking for 20 gallon

[anewbie]

Just some side remarks:

Those are proper species, not subspecies.


The point is: If you have extra tanks to separate the fish, even 40-60 liters are enough for breeding.

I think you over simplify things because one has to have sufficient experience to recognize when you need to sep male/female that are aggressive to each other - the optimal being to put the male and female in 2 different aquariums side by side and move the female when she is ready (this is species dependent because some species the male never or is rarely aggressive to the female even if she is not interested in breeding).

The issue of keeping them together is if there is not room to escape is in the morning things look fine and in the after noon she (or he) is dead.

I think for someone with less experience and a single small aquarium you want species where the male/female are more docile to each other.

Given the large selection of species available you want to weed them down to a few more optimal species.
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For example i don't think you would recommend ortegai in this situation - though in my 65 the male and 3 female did get along quite fine and there was never any visible aggression with all three females eventually spawning at the same time (one female - call her alpha could not telerate the other two but the other two simply went 40 inches away on the other side and they got along together even sharing frys).

[so there was some female/female aggression but it was resolved via distance]

 

[MacZ]

I think you over simplify things because one has to have sufficient experience to recognize when you need to sep male/female that are aggressive to each other - the optimal being to put the male and female in 2 different aquariums side by side and move the female when she is ready (this is species dependent because some species the male never or is rarely aggressive to the female even if she is not interested in breeding).

The issue of keeping them together is if there is not room to escape is in the morning things look fine and in the after noon she (or he) is dead.

I think for someone with less experience and a single small aquarium you want species where the male/female are more docile to each other.

Given the large selection of species available you want to weed them down to a few more optimal species.
-
For example i don't think you would recommend ortegai in this situation - though in my 65 the male and 3 female did get along quite fine and there was never any visible aggression with all three females eventually spawning at the same time (one female - call her alpha could not telerate the other two but the other two simply went 40 inches away on the other side and they got along together even sharing frys).

[so there was some female/female aggression but it was resolved via distance]

In the end I just wanted to abbreviate what you pointed out: Of course you not only need the means to separate the fish, you also need the know-how and time for close monitoring so you can intervene properly if needed.

 

[Mike Wise]

You asked for a suitable pair of apistos for a 20H aquarium and then mentioned rare. None of the pictured species truly combine those requirements for an aquarist not experienced with apistos and breeding. I would suggest starting with A. borellii (Opal), a small adaptable species first. There is always a market for adults. With experience (and more tanks) A. sp. Abacaxis and A. paucisquamis would work and are relatively rare and saleable. Other good selections, but not as salable, would be species of the resticulosa-complex.