Brine Shrimp Not Hatching

[EPAquatics]

Hey all, I am experiencing an issue with hatching out BBS. I have a home-made setup (pictured) consisting of four 1 liter bottles. Each one is completely identical, has a siphon tube and air line/stone connected at the base. The heat is created by a single 25w halogen lamp placed directly in the center of all four bottles, which keeps the bottles between 79-83F at all times. I hatch two bottles per day: one pair today, the other tomorrow, etc. I use Aquarium Co-Op eggs and either Co-Op or Fritz salt at 1tbsp/liter of water, premixed in another container for consistency.

I have been successfully hatching up to 1/2tbsp of eggs per bottle for the last 3 months without incident. Suddenly, one of the four bottles (front right in picture) has given me two consecutive hatch rotations with basically no eggs hatching. All things are exactly the same, down to the amount of air being driven in each bottle. All bottles share the same temperature, brine water source container, egg container, parts, etc. Now one bottle is failing, and only one bottle.

Nothing has changed in months. The only recent thing that happened is that I wiped down the inside of the bottles with my (clean) hand and clean tap water a week ago to remove build-up and slime as part of regular maintenance to the hatchery. All bottles received the same treatment. Why would one our of four suddenly be failing?

I figured that the NERM hivemind would be able to help. Any ideas are appreciated!

[ange]

First of all, sick setup. I really love your stand. When I was doing small scale hatches I had a stand that was nowhere near as nice and now that I have a Ziss I have a completely different arrangement.

Off the top of my head, this is what I would look at for troubleshooting:

• Is it possible that there's some ventilation that messes with one of the bottles due to the angle that it hits?
• What are the bottles sealed with? If you clean with something other than Dawn or a similar product you may have had something leach into the sealant of that one bottle if it was made slightly differently.
• Have you tested your parameters in there? If you mix the water for both bottles in one batch and make sure that everything is properly dissolved this is unlikely, but it's possible that this bottle has routinely had lower salinity or a poor buffer.
• If it's the front right, is it possible that there is contamination going on? It looks like it's right next to some other supplies and being near the front it would be more susceptible.

The eggs that you're using are the same across all of your hatcheries so that variable can be ruled out if you're still successfully hatching. The first thing that I would do is test the water's pH, GH, and KH to see what's going on. I ran into hatching issues recently and it's because my water softener went through some changes that led to the KH dropping below 40 (normally mine came from the tap 180 or higher and I was severely behind on maintenance so this was a complete shock).

If you find that the three parameters that I mentioned are consistent, you can rule that out as a variable for now. After ruling out the parameters affecting it, I would look into contamination. This would probably be from either cleaning procedure (dead brine shrimp potentially causing a hike in ammonia) or contamination as a result of it being in a less isolated position. A good experiment to see if it's the hatchery itself or the positioning would be to swap which bottle is in the front right and see if the problem bottle is the front right bottle, or the specific one that happens to be on the front right at the moment. Hopefully this helps with the troubleshooting process. I don't have any immediate answers but this is how I would go about trying to figure out what's going on.

[EPAquatics]

Thanks for the love ange! It was something I threw together pretty quickly with scraps of painted plywood from an old tank stank. I didn't bother painting the fresh cut edges since it wasn't really necessary, but it works exceptionally well for what it is!
 

• Where the hatchery is, is located in the corner of the room next to a 75g display tank. No ventilation hits it, nor is there anything but water stored near it. I'll post a picture from a wider angle to show the surroundings. The container next to it is what I mix my brine in.
• The bottles are sealed at the bottom with these neat little bottle caps for CO2 reactors that I found on Amazon. They use a silicone rubber gasket to seal. The top of the containers are just the bottom part of the bottles that I cut off when making the system, turned upside down to keep water splashes down and lower heat loss/evap.
• Water parameters are exactly identical across all four bottles, since I mix my brine separately and then pour the mixed water into the bottles from the same container. I wouldn't think that that would be an issue. I live in SoCal, so my water is hard and high pH. Tap is like 8.2ph, 16dGH, 4dKH. It only spends ~24hrs in the bottle before being replaced with new brine.
• When I clean the bottles, I use just my very clean hands and tap water to wipe the sides down with. Nothing but fresh water or brine ever goes in the bottles.
• All bottles are treated the same as far as cleaning is concerned, and this is the only one that's affected.

I'm lost!!!

 

Edited April 24, 2022 by EPAquatics

[ange]

I would definitely recommend trialing swapping the bottles to see if it's the bottle that's the dud or if there's some variable in that location (unidentified so far) that is affecting your hatches.

[EPAquatics]

That was my next step! If I figure it out I'll share what I found!

[EPAquatics]

So, after I made this post, I suddenly stopped having hatching difficulties. Still have no idea what the issue was, but it has returned to normal operation 🤷‍♂️
@ange

[Dancing Matt]

You scared away the gremlins by talking about them.