Daphnia Home Culturing Method
The Container & Water Conditions;
To get my cultures thriving with a view to releasing them into larger quarters outside, I use 3ltr plastic Ice Cream tubs. Into these I place a small margarine tub filled
with coral sand, which helps keep the pH stable.
There are many different angles and formulations out there surrounding the best water conditions for culturing Daphnia, all, I?m sure have valid points. For the purpose
of this article I can only deal with what I use, without getting too bogged down in a
chemistry lesson. True you don?t want your source water to be loaded with chlorine
or heavy pollutants or starved of oxygen. I use rainwater which is adjusted to a pH
7.2 and kept at a temperature (internally) of 72'F.
Initial culture vessel, a 3ltr Ice Cream carton. The first thing I needed to do was to
adjust the rainwater pH up to 7.2
An airline is placed into the tub and set to a very slow bubble as we don't want
heavy aeration because the air can get trapped under the carapace and the Daphnia
will be unable to swim and feed properly. Within this environment the Daphnia
grow and reproduce quite quickly. There will come a time when, with proper management and feeding the culture will become super saturated. The Daphnia are now
ready to be fed to the fish (thinning out) and a 50% water change performed. I have
been maintaining these internal cultures for quite some time now, whilst placing
some of the surplus stock outside in large barrels.