NANFA-L-- Sterilizing water for algae/daphnia cultures

Jase Roberts (
Fri, 21 Apr 2006 11:35:54 -0700

Hi All,

I'm getting starter cultures of "greenwater" algae and daphnia within the next couple days. I'm trying to figure out what water I should use for them and how to treat it (if-in-all). My options for water are city tap water (don't know what kind of chlorination) and river water (about 20 feet from my door). I use the river water for all my tank water changes, but I'm thinking I might not want to use that for the new cultures I'm starting because of the risk of introducing filamentous algae, cyanobacteria, hydra, and other things I really don't want. Same would be true for using old aquarium water from my tanks.

So... should I use aged tap water? I've read that even aged chlorinated water can be bad news for daphnia. Boiled river water? Is there some other good way to sterilize water? UV treatment?

Or am I just overthinking this whole thing? I'd really like to be able to maintain these cultures as pure as posssible. My various attempts-in-setting up greenwater cultures have always been overrun by filamentous algae.

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