Thanks for sharing your method! The method I use does not differ too much from the one you describe but the most important thing is that it always used to work up until two months ago.
After my last post here not much improved and I decided to buy new cysts to see if the problem was there. The result was very interesting: with the new cysts the BBS don't die massively anymore and I get reasonable hatches after 48 hours at 21 degrees. However, I still have a lot more dead BBS than I used to have. So probably the cysts were part of the problem but I haven't figured out what else is affecting BBS survival. I'm also using a pinch of baking soda now but that doesn't seem to have much effect.
All in all it remains a bit of a mystery but the good news is that I have BBS again every day now, even though quite a big proportion of it dies in the bottle.
After my last post here not much improved and I decided to buy new cysts to see if the problem was there. The result was very interesting: with the new cysts the BBS don't die massively anymore and I get reasonable hatches after 48 hours at 21 degrees. However, I still have a lot more dead BBS than I used to have. So probably the cysts were part of the problem but I haven't figured out what else is affecting BBS survival. I'm also using a pinch of baking soda now but that doesn't seem to have much effect.
All in all it remains a bit of a mystery but the good news is that I have BBS again every day now, even though quite a big proportion of it dies in the bottle.