> Even if they are adapted to soft water they would still get more calcium =
> coming to the locality from new water flowing into the locality where =
> the fry are . The problem in captivity in my opinion (no I haven't done =
> any measurements to prove it ) is we don't have water continually =
> flowing in so especially if our water supply is low in calcium to start =
> with, the fry will tend to "use up" the available calcium.
If fry use up as much of the calcium as you suggest then it should be
extremely easy to measure. What's the hardness of Brisbane water?
Around 150 ppm isn't it? Don't you ever water change your fry? That
should also provide some fresh calcium too. If these fish only ever live
in soft water (< 50ppm) then raising them in 150 should be more than
ample. I don't think you will see a significant decrease in hardness
anywhere near to getting below 50 ppm. Even if they do use some of it up
there is still more there than what they ever get in nature. The only
confounding factor here is that we don't what the ratio of Ca to Mg is in
all of this.
Explain your way around that one please. :-)
Peter Unmack