First Breeding Journal: Longfin Leopard Danios

[Odd Duck]

@benchilton Where are you?  Maybe there will be someone that has some that is close and will notice this.  You never know!

[Ben C.]

@Odd Duck I'm in the DFW area!

[Odd Duck]

Well so am I and I have cultures of both!   My microworms are neglected and sad right now, but I can fix that quickly.  I was already planning to do that today, just got overcome by an attack of lazy.  
 

Vinegar eels are easiest to harvest from a bottle with a fairly long, narrow neck like a beer or wine bottle.  I used one soy sauce bottle, the empty apple cider vinegar bottle, and a fruit fly culture deli cup.  I’ll just dump a bunch into an empty water bottle for you for transport.

And I’ll start a fresh microworm culture for you right now.  I also have white worm cultures ready to go.  Any interest in one?

[Odd Duck]

@benchilton  Cultures are ready whenever you are.  I’m in North Richland Hills.  What part of DFW for you?

[Ben C.]

@Odd DuckOh that would be amazing! I can't get them today - but how hard is the vinegar eel setup? Just half cider, water, and apple pieces? I would prefer to take those.

 

I'm in Allen, which is unfortunately quite far haha. Used to work in Fort Worth though so I know the drive pretty well though.

Edited July 6, 2021 by benchilton

[Odd Duck]

@benchilton yes, on the vinegar eels.  They are smaller than the microworms, but easier to culture.  Slower growing, though, and may not keep up unless you have several cultures.

I have your cultures ready whenever you are.  I’m currently working from home, so whenever.  I do have an appointment tomorrow, though.  But anytime after about 4:00.  I might be available earlier, but can’t be certain since I don’t know for sure how long the appointment will take.

Edit to add the photo of a list I put together.  The vinegar eels are so skinny that you get an impression of movement but I can’t really see them as individuals in culture.  I can see individuals once swirled in water and more spread apart, but they are smaller than the microworms.  The microworms are a bit more substantial but still really an impression of movement when together, but you can easily see individuals once swirled in the water.  The microworms are a bit more fidgety to culture but much quicker and easier to harvest.  Vinegar eels are dead easy to culture, but much more fidgety to harvest.

Edited July 7, 2021 by Odd Duck
To add photo of sizes of common live foods.

[Ben C.]

@Odd Duck awesome I'll send you a message!!

[Torrey]

@benchilton I have been breeding zebra danio (even smaller than leopard danio fry). My best success has been to keep fry in betta cups that I used Dean's panty hose trick on the bottom, and float in a 10 gallon tank.

 

Otherwise they seem to expend more energy swimming and looking for food, than they actually can eat.

Once they stop looking like eyelashes with a pair of eyes, and you can actually see their bellies, they are ready for bigger foods like BBS.

Here's my steps for successful hatch and survival of fry:

1. Only the bare glass bottom of the spawning tank needs to be cleaned. A healthy biofilm on the glass sides will greatly improve fry survival. 

2. Maintain a tank of green water at all times. Less problematic (and way less stinky) than infusoria.

3. Maintain a colony of detritus worms, which are easier to keep going than vinegar eels.

4. Freshly hatched fry will first attach to sides of the tank and feed on the biofilm. (This is why a healthy amount of biofilm in an established tank is critical to success)

5. Once they start free swimming, move them into cups (I catch them in a cup and pour in) to minimize wasted food/ overfeeding risks

6. First week of food needs to be micron sized. Boiled egg yolk/Aquarium Co-op fry food / high quality flakes / Bug Bites in a blender with boiled water (I freeze leftovers on a piece of parchment paper in drop form) or green water and feed a drop or two per cup (need the water in the cup to get cloudy) every few hours first week.

7. 50% water changes 2x a day for the first week. 

8. By the end of the first week, they are generally ready for free swimming in the tank (I use a 10 gallon) and can start BBS, microworms, etc, in addition to the green water (or the rest of the frozen drops above). Feed at least 4x a day.

9. By the 3rd week, you can offer fry food, or finely crushed flake food. They should eat until you see nice, full bellies, at least 4x a day.

10. I run 2 large aquarium Co-op sponge filters, and do at least 2 water changes each day because if you are feeding enough for sufficient growth, they foul the water rapidly!

 

Next batch will be easier, and then you will establish your own rythm. 

[Ben C.]

@Torrey this advice is fantastic, thank you! Looks like they're ready to spawn again, so I will incorporate this into my next batch! I can see big round stomachs now on the first hatch (down to 4-5 now unfortunately, but eating dried food),  I tried BBS but they didn't seem interested yet. I like the cup idea though - it did seem like they were spending a lot of energy to swim even in a 5 gallon with a tiny sponge filter. I got tons of micro food from @Odd Duck today and I'm excited to try again! I'll keep updating.

[Ben C.]

Update: the fated 4 of the first batch ate their first BBS today! Slow going but they look like real fish now...impossible to photograph in the large aquarium, but I did my best. 

 

The first fry of the second batch hatched out today, and I'm definitely more prepared this time! 

[Odd Duck]

@benchilton  Nice!

[Torrey]

@benchilton congratulations!

 

My fry are 8 weeks old now, and heading off to new homes soon😥

 

It's bittersweet, I love watching them before bed every night.

 

Your littlest baby stuck to the glass is [ideally] feeding on biofilm on the glass. That's the benefit of a seasoned aquarium for fry. In my experience, the more biofilm available at that stage, the higher the success rate of the fry.

 

So happy for you!

 

[Pardon the dirty tank, fry require twice daily cleaning. I want the auto change system now, lol]

[Ben C.]

@Torrey thank you! Your little ones are beautiful - I would be sad to part with them too! Guess that bittersweet day is hopefully coming for me soon too...

These fry are hatching out in a tank that has been set up for 8 months now. Hopefully that will help - I see 6 more today, with probably many more on the way...

[Ben C.]

Big orange bellies full of BBS, growing really fast now! New babies took their first swim today, took residence in the far back amongst the lettuce roots which prevents photos...but I'm sure there is plenty in this tank for them to eat for now, I will start adding microfoods once I see more start swimming around- only 2 or 3 right now. 

[Ben C.]

Question to the hive mind of those that may be following - as these new babies are hatching out, I'm worried about flow being too high. I'm currently using an aqueon air pump 10 with a sponge filter in a 10 gallon aquarium. As they are taking their first little swims, they're being blown around, which worries me - I also worry about them ending up too spread apart to make feeding simple. I've turned off the pump for now, but will that negatively affect the water or their development? For reference, it's a bare bottom, been seasoned for 8-9 months now, with the water surface covered in a variety of floating plants, plus with hornwort for nitrate control. Thanks y'all!

[Ben C.]

They grow up so fast...

[Ben C.]

First batch is now 4 weeks old - their eyes are the most radiant baby blue, along with a matching stripe right down their body. Hard to believe this is what they look like as youngsters - I'm going to miss it! Still impossible to photograph with my phone, but alas. 

 

Second batch is about 10 days old now, feeding micro foods 4 times a day. Hard to monitor in such a large space, but if I walk away with more than the first, I will be happy. 

[Ben C.]

One additional outcome of all of this is I've really got my baby brine shrimp "recipe" worked out - I was using my tap water or aquarium water, and being Texas water, it's just so incredibly hard. I realized that adding reef salt, with all the additional minerals was causing a ton of dead shrimp before I could even collect them. Now that I'm using RO water (my brother does saltwater tanks so I just grab some 5 gallon buckets from him) and adding the reef salt, plus a dash of Prime both when I set it up and at the 24 hour mark, and it's night and day. Great hatch rate, and little waste. Experimenting with adding garlic oil, vitachem, spirulina powder, etc. for fun, but it's nice to know I can use less eggs to get more shrimp now!

[Ben C.]

5 weeks old today, got all their fins and they're beginning to fill in. Beginnings of more active behavior!

A little disappointed though as the second batch failed - not sure what went wrong, but the fact that they were so spread out I believe was the issue. It was hard to target feed them, leading to more wasted energy swimming around, and me overfeeding. Just carelessness I suppose. I've caught out the final 3 remaining and moved them into the Co-Op's specimen container until they get bigger. 

Fortunately, if all of these fry make it, I will have a nice sized school with the adults that spawned them added together, which was my ultimate goal. These are really not a "for profit" fish - the labor of all the feedings, etc. does not add up for a fish that regularly sells for $1.99 or so...

[Torrey]

I just took ~ 10-15 fry to my lfs for more plants.

 

I discovered one of my females carried the fainting gene, so her fry **did not** go to the LFS.

Since I am working on a dwarf line, I kept the smallest fish to breed for my 6th generation. I need to bring in a fresh, longfin melanuestic (sp?) so I don't end up with an inbred line.

Shockingly for an unplanned spawn, 90% of the fry made it.

New lfs manager was thrilled with quality, size and coloring.

Since I am going for a smaller version (my breeding adults are now 3/4 of the length of typical zebra danios, and the ones I kept are half that size) with flashier coloration, even my "not quite there yet" fish turned out pretty nicely. 

My trick to improve fry survival is catch wrigglers with a nasal syringe, or use a bit of airline tubing on an infant medicine syringe. 

Suck babies up, and place in the specimen holder with the nano foam filter in it.

Use a Ziss air diffuser, and use a valve to control air flow. For the first two weeks, turn down the air flow when you feed. Turn it up sufficiently to create a mild flow, but not enough to throw the babies about.

In quarantine last year, I made fry specific sponge filters with airline straight into a prefilter fine foam. Requires very little airflow to do the job for up to 10 fry, and if well seasoned first, provides enough bio film to feed the fry for almost 3 days.

 

Use a medicine dropper to feed the fry, and only give one drop at a time. Anything not finished in 5 minutes, use a nasal syringe to remove.

Discharge the nasal syringe into a betta cup, and check for fry before dumping😅

[Ben C.]

On 7/30/2021 at 12:36 AM, Torrey said:

I just took ~ 10-15 fry to my lfs for more plants.

 

I discovered one of my females carried the fainting gene, so her fry **did not** go to the LFS.

Since I am working on a dwarf line, I kept the smallest fish to breed for my 6th generation. I need to bring in a fresh, longfin melanuestic (sp?) so I don't end up with an inbred line.

Shockingly for an unplanned spawn, 90% of the fry made it.

New lfs manager was thrilled with quality, size and coloring.

Since I am going for a smaller version (my breeding adults are now 3/4 of the length of typical zebra danios, and the ones I kept are half that size) with flashier coloration, even my "not quite there yet" fish turned out pretty nicely. 

My trick to improve fry survival is catch wrigglers with a nasal syringe, or use a bit of airline tubing on an infant medicine syringe. 

Suck babies up, and place in the specimen holder with the nano foam filter in it.

Use a Ziss air diffuser, and use a valve to control air flow. For the first two weeks, turn down the air flow when you feed. Turn it up sufficiently to create a mild flow, but not enough to throw the babies about.

In quarantine last year, I made fry specific sponge filters with airline straight into a prefilter fine foam. Requires very little airflow to do the job for up to 10 fry, and if well seasoned first, provides enough bio film to feed the fry for almost 3 days.

 

Use a medicine dropper to feed the fry, and only give one drop at a time. Anything not finished in 5 minutes, use a nasal syringe to remove.

Discharge the nasal syringe into a betta cup, and check for fry before dumping😅

you really have this down to a science! I gotta get me some more equipment haha. That's really cool about the dwarf line - sounds really interesting! What is the fainting gene though?

[Torrey]

Apparently, zebra danios are really close to humans in a lot of genetics?

So close that they are used in research, including research on anxiety (freeze/faint, fight, flee etc)

When I went to catch the fry in the net, 25% of one female's line fainted. If there was a local research team, I would ask if they wanted the line.

 

It's a double recessive gene, like the nacre gene for color. It means two things: it showed up because I crossed grandsons back to the original female to double check any possible genetic problems (which showed up only in the fainting gene), and the offspring have a cellular memory of nets being traumatic from their grandmother being caught.

 

Which is actually pretty cool, from a research perspective. 

 

Not so cool to take fish that go belly up when they get scared to the pet store though 😅

 

This is why responsible line breeding requires so many tanks to separate out fish, and so many tables / spreadsheets to keep all the breedings straight.

 

It doesn't *have* to be done that way. 

 

It's much easier to identify potential problems if it is done that way. 

[Ben C.]

On 7/30/2021 at 6:23 PM, Torrey said:

Apparently, zebra danios are really close to humans in a lot of genetics?

So close that they are used in research, including research on anxiety (freeze/faint, fight, flee etc)

When I went to catch the fry in the net, 25% of one female's line fainted. If there was a local research team, I would ask if they wanted the line.

 

It's a double recessive gene, like the nacre gene for color. It means two things: it showed up because I crossed grandsons back to the original female to double check any possible genetic problems (which showed up only in the fainting gene), and the offspring have a cellular memory of nets being traumatic from their grandmother being caught.

 

Which is actually pretty cool, from a research perspective. 

 

Not so cool to take fish that go belly up when they get scared to the pet store though 😅

 

This is why responsible line breeding requires so many tanks to separate out fish, and so many tables / spreadsheets to keep all the breedings straight.

 

It doesn't *have* to be done that way. 

 

It's much easier to identify potential problems if it is done that way. 

That's actually really cool, while unfortunate for the fish, very cool. Would've never known haha

[Torrey]

Neither did I until I had so many babies go belly up when I caught and bagged them!

 

Now they are happily swimming around without a care in the world. 

 

Since they are ~half the size of regular zebra danios, I am using the babies who don't faint to breed, then crossing back in to ones who do faint to identify which ones are carriers, and slowly remove the carriers from my breeding stock.

 

Fun times, lol

[Ben C.]

@Torrey a lot of work but sounds totally worth it! Even smaller danios means bigger schools of em!