How to Modify an Airstone

[jewett]

Hi all, I have read in a few different places on the forum about modifying an airstone to be used for Daphnia culture aeration. But I cannot seem to find how to modify. I have placed a C-clamp onto the airline tubing to help slow down the air flow and it does produce bigger bubbles now, but I have had my water flea culture a week and though I can see them still swimming around in the tub they have not seemed to multiply as I had expected. I was thinking about purchasing the Bio-foam filter mentioned in John Clares culturing article in CC but I would prefer to use equipment I already have and safe some money! So any tips on airstone modification are much appreciated.
Thanks in advance,
Heather

 

[RobM]

I'm sorry I don't know how to modify the airstone, but couldn't you just use an open airline? it would then produce big enough bubbles not to harm the Daphnia.

 

[Jennewt]

I've used airstones (set to just trickle) and also open airline (no airstone) in daphnia tubs. I don't see any difference. But these days I just use open airline so I never have to replace the airstone. I would look for other possible causes for the slow reproduction, such as cold temps or short light cycle. Also, I wouldn't really expect to see any noticeable increase in their numbers in one week - it takes a while for them to settle in and start cranking out offspring.

 

[jewett]

Thanks for the responses. I think I will just go with an open airline. And the water temps are fairly cool, about the same as my newts - around 15C. And I keep a light fixture on over them 24/7. I will try to be more patient for the culture to propagate!
Heather