[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Water treatments

> Date: Tue, 5 Mar 2002 22:31:26 -0600
> From: Douglas Guynn <dguynn at nwol_net>
> Subject: Water treatments
> I would like to start a daphnia culture, but I have a problem with my tap
> water. It is VERY hard, 34 GH, and alkalinity higher than most 8 KH. I
> dilute the tap water with RO water 1:1. Also, the city adds chloramine to
> complicate things.

Daphnia, IME, seem to prefer quite hard water. I'm a little puzzled that
your GH is so much higher than the KH. They need Ca for their shells, I
think. If the GH kit is measuring some non-hardness stuff (e.g., salinity)
you may not want to use any RO water at all.

> What is the best thing to use for removing the chloramine from the water
> for use in culturing daphnia? Sodium thiosulfate?

Why do you want to remove it?

Either don't remove it, or use sodium thiosulfate and age (with vigorous
aeration) to dissipate the ammonia released from the chloramine. Don't use
dechloraminators like Ammo Lock 2, Amquel, Prime, etc. as they do kill

I don't think Dapnia have any problem with modest amounts of chloramine, but
I have not tested with anything above about 2 ppm.


Wright Huntley -- 650 843-1240 -- 866 Clara Dr. Palo Alto CA 94303 

   Instead of giving money to found colleges to promote
   learning, why don't they pass a constitutional amendment
   prohibiting anybody from learning anything? If it works as
   good as the Prohibition one did, why, in five years we would
   have the smartest race of people on earth. -- Will Rogers