Brine Shrimp Dying In First Hour

[UTJeeper]

I have been successfully hatching Aquarium Co-op green tin brine shrimp in a Ziss hatchery for months to use as food for my Apisto fry. Things had been going fine for months and then all the sudden about 2 weeks ago my hatches starting dying and sinking to the bottom of the Ziss hatchery. I am still getting a good hatch rate, they just die within an hour of hatching some almost immediately.

• I tried scrubbing the Ziss hatchery real well, both with just fresh water and also with dish soap and a thorough rinse.
• I fill water to the same level, about 1 inch from the top.
• I have kept the salt constant with 2Tbsp of instant ocean that I've been using all along. I let it dissolve for 1 hour before adding eggs.
• I have kept the temp constant with the aqueon 5w mini heater at about 29C, I observe the temp several times a day.
• I tried RO water to eliminate a change in water quality from the tap as an issue, no help.
• I tried different air volume, less aggressive, more aggressive, no help.
• I even tried a different brand egg, BNYEE eggs hatched and died too.

Any ideas on what would cause this to happen? Until 2 weeks ago I was getting nice healthy hatches for months. Thanks for the help!

[Guppysnail]

Could something like an aerosol being sprayed have contaminated the salt?  Is it a new batch of salt that may be contaminated?

[UTJeeper]

Aerosol probably not, but I did just break into a new bag of the sea salt around that time. It is the same brand I have been using but did not think about the salt possibly being bad. I guess I'll try a batch with different salt to eliminate that as the issue. Thanks for the idea.

[UTJeeper]

Update, so I added a second Ziss hatchery with the goal of changing the process. So I filled Ziss #1 with RO water and 2 Tblsp of Instant Ocean. I then let it sit overnight and add eggs after I get home from work in the PM. When I add eggs to #1 I then setup #2 with RO water and salt and let it sit overnight. So each day I am harvesting from one hatchery and reset it while I am adding eggs to the other. For some reason this has worked to keep my hatches alive.

For whatever reason I needed to let the temp and salinity settle in for a long period of time before I add eggs. That cycle time required two hatcheries so that I have a hatch every day. Anyway, I thought I would document what worked so that any other newb in the future might learn from my trial and error. 

[Kj299]

I’m glad I found this thread because I’m going through the exact same thing. I went months and months hatching with great success and then all of a sudden boom, hatching rate is great but the BBS die very quickly and fall to the bottom of the hatchery. I have tried all sorts of things, baking soda for ph easy brine shrimp salt instead of fritz salt. Heater, no heater, new eggs, longer and shorter amounts of time hatching and always the same, great hatch rate but they die so fast. I have a second hatchery so I’m going to try what worked for you and let the salinity and heat settle over night and put a batch in tomorrow! 
 

OP if you happen to see this please comment back if you’ve been having continued success with this method of waiting before putting in the eggs! I’m running out of patience and ideas of how to get a good supply of BBS for my apisto fry! 
 

thanks! 

[AllFishNoBrakes]

@Kj299 While I didn’t start doing it because of BBS dying, I set up my hatchery the night before, and then add the eggs the following morning. I let them sit for 36 hours, harvest, and don’t have any issues. 
 

It simply works better with my schedule to set it up the night before and then add eggs in the morning, so I can harvest the next night when I get off work. I don’t think it hurts that the salinity and temp regulate overnight before adding the eggs 

[Kj299]

That makes sense. I normally do a 24 hour hatch time. I’ve tried 36 hours but even still they’re all dead. The hatch rate itself is great but the BBS just aren’t surviving like they should.
 

As mentioned before I had months of success with Fritz salt and a 1:1 ratio salt to eggs but over the last month I just can’t seem to get a hatch to survive. Recently I did have one singular good hatch using marine salt and a 2:1 ratio 24 hr hatch time but that doesn’t seem to be working now either.

 

I’m stumped honestly. After scouring the internet I’ve read tales of people with the same issue some get a fix some don’t. At this point I have to assume there’s something in my water that I can’t test for that’s causing this to happen. Parameters out of my tap are ph 6.8, ammonia 0, nitrite 0, nitrate 0 kh 3° gh 6° (which of course these change with the added marine salt). I don’t assume it’s copper because all of my tanks have snails in them that are thriving. I’m not sure what else I can even test for at this point. Hoping to get a lucky break somewhere and have my hatches return to normal 

[Schuyler]

I've heard that if you're air is too strong then it can break they're little flappy things so they can't swim.

I just put pickling salt and eggs in a 2 liter, pour in straight trap water, and then add air. 

[Kj299]

Interesting I’ve never heard of that 🤔 I’m in the process of trying what OP said and letting the hatchery sit before putting in the eggs but if that doesn’t work I’ll try adjusting air flow as well. I normally use a ziss airstone and tetra air pump, I’ve also tried no air stone. 

[AllFishNoBrakes]

I will say that I keep my air pretty low. Even using the nano usb pump I turn it down to just a nice steady stream that keeps everything moving throughout the tumbler. 

[Kj299]

I’ll keep this in mind! I have one if the nano pumps so I’ll test it out, no harm In trying something new, my hatches can’t get any worse lol 

[Galabar]

I have the water premixed (with Instant Ocean) in a separate container.  So, I'm always ready with new water.

Also, I think the preferred salinity for brine shrimp is between 1.024 and 1.028.  You can double-check to see what you have.