3 failed BBS hatches in a row...

[Brandy]

Hi all. Using ACO bbs, aquarium salt and baking soda. 3x in a row my hatch has largely failed. I had incredible success previously, and suddenly am getting less than 10% hatch...over a 24h window.

I actually looked really closely at the floating "shells" It is about 50% dead hatched brine. I am flummoxed. So they hatch and...die? Why? 

Baking soda and salt have not changed. I changed out my nano air pump for a new one...can the air flow be too high? Or temp? It is about 80-81...provided by a incandescent bulb, that is only on in the day. I suspect it gets cooler at night.

Edited February 14, 2021 by Brandy

[Fonske]

18 minutes ago, Brandy said:

can the air flow be too high? Or temp? It is about 80-81

I would suspect the air flow. My hatchery runs at above 80 all the time, never had a problem with that. Changes in aeration, however, did cause some problems. I'd guess that the excessive flow damages the shrimp and maybe the eggs too by crashing them repeatedly into the walls. (Disclaimer: my BBS are not from Aquarium Coop).

[TheDukeAnumber1]

I very much doubt air flow is the problem. Check out how much air this fish farm uses. I use a lot of air flow too.

https://youtu.be/mKclGdn3ijc?t=789

I would look for another factor. What's your recipe, can we see the setup, maybe try filtered water to rule that out?

Edited February 14, 2021 by TheDukeAnumber1

[Philip]

5 minutes ago, TheDukeAnumber1 said:

I very much doubt air flow is the problem. Check out how much air this fish farm uses. I use a lot of air flow too.

https://youtu.be/mKclGdn3ijc?t=789

I would look for another factor. What's your recipe, can we see the setup, maybe try filtered water to rule that out?

I saw that video and was shocked at the amount of air they use. I crank mine up now. 

[Cory]

It almost always boils down to something is different. This is no different then my fish died. Start with water parameters etc.

 

this time of year, temps are colder from the tap, hatch may be getting colder at night. Water parameters from the tap can change over the year. Making sure the Hatcher is cleaned if bacteria was allowed to build up. Also waiting up to 36 hours could help as well if it’s a bit cold.

when repeating something and then there is a different result. It almost always means there is a change. 
 

While it’s unlikely too much air will harm the eggs, as shown in a topical fish farm. Air does lead to evaporative cooling. So speeding up chilling of the water, with night time temps dropping could cause this possibly. Especially if taking a temp from months ago vs tonight at 3am etc. just gotta play detective.

[Brandy]

So I think Cory nailed it. I lowered the airflow and immediately the hatch rate is back up. I suspect that cooler temps at night plus the boiling level of airflow was at least slowing my hatch, and also pushing eggs up on the side of my container, where they may have dried out. I am back to a beautifully gold hatch, and my fish thank you all, especially the fry.