Platys Mollies and other live bearers

"NetMax" wrote in message
.. .

Other than the Mollys, their dependance on salt is probably artificial.
Raising livebearers in very hot salty water benefits the growers in 2
ways. The combination of salt & heat reduces the number of pathogens
which will survive (less bacterial and viral diseases) and increases
their metabolism and appetite, (so they grow faster).

Do I need to be concerned about their ability to adjust to life
without
salt? And is it really necessary to put all that salt in the water
for
live
bearers other than Mollies?

Yes, and now, yes (until acclimated). You can try to get them off salt
slowly, but for livebearers born in brackish water, I think your best
success will be with their fry.
--
www.NetMax.tk

OK, I just did a little experiment. I have these five 20g tanks, and the
water is soft 3dgH, 3dkH and 7.7pH (not exactly paradise for
livebearers). I usually put 1/2 cup marine salt into a 60g tank, but I'd
put 1 full cup of marine salt into each 20g tank. That's 48 teaspoons or
2.4 teaspoons per gallon. I then stocked the tanks with Guppies (that
I'd had for several weeks are were very sickly), Balloon Mollies &
assorted Swordtails (which I'd had for many weeks and were very healthy
but acclimated to 100% freshwater), and Saffron Mollies & Starburst
Platys (new delivery from Singapore).

It's only been six days, but so far I have no regrets. The Guppies don't
look better or worst but haven't been dying (which is an improvement).
The freshwater acclimated livebearers haven't missed a beat (appetite
activity colouration all excellent). Most surprising is that the new
arrivals look really great. Lost two within a day, but those didn't look
good at arrival, and the delivery was about 100 fish.

This experiment is working out nicely, but 2 problems. I took those
tanks off-line so the automatic water changer would not dilute the
salinity. I'll need to make up a manual schedule with a salt
replenishment program. The 2nd problem is what to do next. I can post a
sign so customers know that they are in brackish water (I think this
concentration is brackish). I'd like to acclimate them to freshwater,
but with all the fish deliveries every week, I cannot coordinate the
acclimation of several tanks at different stages.

I'm open to ideas. I might try to adjust the salinity downwards. I
think I'm at around .24% right now, and if I can get the same results at
.1% then acclimation to freshwater will be easier for customers.
--
www.NetMax.tk



Thank you for your extremely well answer to my question! Looks like I can
conclude that only the Molly is originally meant to benefit from salt, but
the development goes in the direction of using salt for all live bearers.
When I hear about your experiment I can see why they do it too.

The Platies I did buy are still alive and healthy, but they do not get any
salt in the water. I don't hink my Angels and Pleco would apreciate that one
bit

Maybe it depends on how many fish pr gallon the tank has, as to how obious
the benefit of salt is? LFS's (and of course breeders) have quite a few
fish in every tank, compared to my fairly sparingly populated tank.

Thanks again NetMax, as always