Apogon Parvulus / Red Spot Cardinals breeding! Help!

[vaguelyreeflike]

In our work tanks I have a school of 6 red spot cardinals (apogon parvulus, but some sources say ostorhinchus parvulus?) and one of them has a fat mouth full of eggs! He(?) briefly spat them out partially and immediately pulled them back in so I did get a visual confirmation on them, theyre silver and i swore i saw itty bitty black dots in them but that could just be me.

Theyre in a 20gal cube with a purple dottyback, I can move it though. But theyre connected to the sump system so I dont know if babies would get pulled through the downpipe.

Any tips or advice?? Can I move him into a breeder box? I dont have an egg tumbler so I do not want him dropping them.

SOS.

 

[vaguelyreeflike]

After doing some reading the babies are going to be planktonic for a while so Im not exactly confident Ill be able to even house them, I do have a special breeder box I made specifically for amano shrimp larvae so I may try that. What can I even feed them??? Reef roids??

I’m freaking out y’all

 

[ISpeakForTheSeas]

In our work tanks I have a school of 6 red spot cardinals (apogon parvulus, but some sources say ostorhinchus parvulus?) and one of them has a fat mouth full of eggs! He(?) briefly spat them out partially and immediately pulled them back in so I did get a visual confirmation on them, theyre silver and i swore i saw itty bitty black dots in them but that could just be me.

Theyre in a 20gal cube with a purple dottyback, I can move it though. But theyre connected to the sump system so I dont know if babies would get pulled through the downpipe.

Any tips or advice?? Can I move him into a breeder box? I dont have an egg tumbler so I do not want him dropping them.

SOS.

After doing some reading the babies are going to be planktonic for a while so Im not exactly confident Ill be able to even house them, I do have a special breeder box I made specifically for amano shrimp larvae so I may try that. What can I even feed them??? Reef roids??

I’m freaking out y’all

Sorry, I didn't have time to respond last night, and my answer is a bit disorganized. I hope it helps regardless.

Ostorhinchus parvulus is (to the best of my knowledge) the currently accepted taxonomic name, so Apogon parvulus is an unaccepted synonym.

A quick note on mouthbrooders - I don't know if it would be best to move the male now or not (ideally you would time it so you move him just before the eggs hatch, but you would need to know how long it takes for them to hatch to time it properly), but you will need to have a separate tank for the larvae (the babies).

As a quick note (this is discussed below, but I figured I'd mention it up here to make it gets noticed), rotifers work for some fish, but not others. Based on the lack of cardinalfish aquaculture info I can find and the fact that the closest related cardinal to this one that I know of that was aquacultured was reared with the most success on copepod nauplii, I would assume rotifers don't work for rearing these guys, but I'd probably offer them both rots and pods anyway in case they do work (as rots are generally easier to culture than small pods).

Now, with that out of the way, I'm going to dump a ton of general breeding advice on you (some of which may not apply to mouthbrooders, but most of which will):

"Based on this, I'd assume you'll probably need more than rotifers - I'd guess you'd need Parvocalanus crassirostris pods (or other, super tiny pods - but Parvocalanus are by far the easiest to find on the market at the moment), and you'll probably build up slowly from Parvo nauplii to Artemia nauplii over the course of the rearing.

Some general advice that might help:
- Have a tank ready to move the larvae into (basically a tank with an air stone, a dim light, and a heater - a kreisel tank is ideal, but not necessary; you don't want a filter, a skimmer, uncovered pumps/powerheads, etc. - it needs to be as pelagic larvae safe as possible).
- Be prepared to catch the young when they hatch (ideally, you'd be able to move the eggs immediately before hatching into the new tank, but I'm assuming you don't know exactly when they'll hatch) - catch them and move them into the larval rearing tank as soon as possible.

ISpeakForTheSeas said:
Assuming you have fertile eggs, the advice I would give is this:
- if possible, get some Parvocalanus crassirostris pods too (rotifers are great, and I would expect the larvae to go for them, but some fish larvae are picky and prefer pods over rotifers - having both seems like a good way to ensure you have good, small foods for them... Artemia and other larger pod species would likely be good to have on hand too for the larvae as they grow.

- Get various sizes of very fine sieves so you can control the size of the feeders being offered to the larvae as/if needed.

- Add phyto directly to the larval rearing tank. It’s a good method of ensuring that the feeders are gut-loaded and healthy, and it makes them easier for the fish to see (better feeding/survival rates are typically observed with this method).
- Observe and note information about the larvae (things like how big the eggs are, how big the larvae are, when the larvae settle, when coloration comes in, etc.) and the larval behaviors (stuff like if they are attracted to light, how they react to light, if they are attracted to certain colors, what feeders they eat and what what sizes of feeders they eat at what days post hatch, what kind of substrate they prefer to settle on, are they cannibalistic, etc.).

- Watch for developmental bottlenecks and issues with your rearing methods.

- A lot of people run into feeder issues their first few times breeding, so I’d have a backup plan in place to be able to get some feeders quickly if you find yourself needing some.

With regards to the sieves and feeder sizes:
- You may need to screen the feed initially to only offer Parvocalanus nauplii.
- Observing the larvae eating when/if possible is important for telling if they are accepting/able to eat the food you are offering them.

ISpeakForTheSeas said:
Generally the main thing to watch for at this stage is a bottleneck where the young start dying off - these usually happen after a few days (day three post hatch seems to be one of the most common bottleneck days for fish that hatch with a yolk they can feed off of - if the rots and phyto don’t provide the proper nutrition for these guys, you might see a die off sometime around here). Some fish run into multiple bottlenecks, including some that happen around/after 2-3 weeks post hatch, so you really need to keep an eye on how things are going. Bottlenecks typically occur because the food the fry is eating isn’t nutritious enough for them, or they’re not interested in eating the food offered, or the food isn’t the proper size for them to eat.

ISpeakForTheSeas said:
if you do run into a bottleneck and lose this batch, don’t get too disappointed by it - this happens frequently in trying to breed a new species (even to the professionals), and every attempt gets one step closer to success.

With regards to the substrate settlement:
- Some species need sand, rock, dark areas, specific colors, or other oddly specific things to settle on/in (from what I've seen, inverts are usually a lot more picky with this), so it may help to have a ledge or cave (PVC should be fine for this, if it's even needed, which I honestly kind of doubt) and a little sand in the larval rearing tank.


That’s all I can think of at the moment - hope it helps!"

 

[vaguelyreeflike]

Sorry, I didn't have time to respond last night, and my answer is a bit disorganized. I hope it helps regardless.

Ostorhinchus parvulus is (to the best of my knowledge) the currently accepted taxonomic name, so Apogon parvulus is an unaccepted synonym.

A quick note on mouthbrooders - I don't know if it would be best to move the male now or not (ideally you would time it so you move him just before the eggs hatch, but you would need to know how long it takes for them to hatch to time it properly), but you will need to have a separate tank for the larvae (the babies).

As a quick note (this is discussed below, but I figured I'd mention it up here to make it gets noticed), rotifers work for some fish, but not others. Based on the lack of cardinalfish aquaculture info I can find and the fact that the closest related cardinal to this one that I know of that was aquacultured was reared with the most success on copepod nauplii, I would assume rotifers don't work for rearing these guys, but I'd probably offer them both rots and pods anyway in case they do work (as rots are generally easier to culture than small pods).

Now, with that out of the way, I'm going to dump a ton of general breeding advice on you (some of which may not apply to mouthbrooders, but most of which will):

"Based on this, I'd assume you'll probably need more than rotifers - I'd guess you'd need Parvocalanus crassirostris pods (or other, super tiny pods - but Parvocalanus are by far the easiest to find on the market at the moment), and you'll probably build up slowly from Parvo nauplii to Artemia nauplii over the course of the rearing.

Some general advice that might help:
- Have a tank ready to move the larvae into (basically a tank with an air stone, a dim light, and a heater - a kreisel tank is ideal, but not necessary; you don't want a filter, a skimmer, uncovered pumps/powerheads, etc. - it needs to be as pelagic larvae safe as possible).
- Be prepared to catch the young when they hatch (ideally, you'd be able to move the eggs immediately before hatching into the new tank, but I'm assuming you don't know exactly when they'll hatch) - catch them and move them into the larval rearing tank as soon as possible.

With regards to the sieves and feeder sizes:
- You may need to screen the feed initially to only offer Parvocalanus nauplii.
- Observing the larvae eating when/if possible is important for telling if they are accepting/able to eat the food you are offering them.


With regards to the substrate settlement:
- Some species need sand, rock, dark areas, specific colors, or other oddly specific things to settle on/in (from what I've seen, inverts are usually a lot more picky with this), so it may help to have a ledge or cave (PVC should be fine for this, if it's even needed, which I honestly kind of doubt) and a little sand in the larval rearing tank.


That’s all I can think of at the moment - hope it helps!"

Thank you so much for all of this information, it’s super helpful!!

 

[Soren]

In our work tanks I have a school of 6 red spot cardinals (apogon parvulus, but some sources say ostorhinchus parvulus?) and one of them has a fat mouth full of eggs! He(?) briefly spat them out partially and immediately pulled them back in so I did get a visual confirmation on them, theyre silver and i swore i saw itty bitty black dots in them but that could just be me.

Theyre in a 20gal cube with a purple dottyback, I can move it though. But theyre connected to the sump system so I dont know if babies would get pulled through the downpipe.

Any tips or advice?? Can I move him into a breeder box? I dont have an egg tumbler so I do not want him dropping them.

SOS.

This would be amazing if you succeed! These fish are still near the top of my list for a small "school" in my 125g display.
Though I don't have any experience as of yet, breeding fish is of great interest to me.

 

[vaguelyreeflike]

This would be amazing if you succeed! These fish are still near the top of my list for a small "school" in my 125g display.
Though I don't have any experience as of yet, breeding fish is of great interest to me.

I don’t have high hopes as these don’t seem to have any recorded instances of success in home aquariums yet, but fingers are crossed!!

 

[sabeypets]

According to Witt's book: "All known species of cardinalfish are mouthbrooders that orally incubate their eggs until hatching 7 to 8 days after fertilization. With the exception of the Banggai cardinal fish that lacks a pelagic larval phase...". I would try feeding the larvae Parvocalanus crassirostris and/or Apocyclops panamensis nauplii.

 

[DaJMasta]

I don't know how big they are, but if they are actually like banggai cardinals, they won't need copepod nauplii - the fry will be developed enough out of the mouth that they can eat larger foods - even grown standard copepods - and may start accepting very small prepared foods within a week or two (often early on they need live foods because the movement triggers their feeding response).

If you can catch the male with the eggs when they are about hatching (try and see if someone has a hatch timing available, otherwise it's observation and best guess, and trapping is less stressful than netting) and keep him in a mesh box or separate tank, he should spit them out and start going back to eating in the next day (and offering some food to him can be a way to check if he's got them all out if you can't otherwise tell). If they're like banggais, the fry released may not have their swim bladders fully developed (it depends, I think they normally should), but should be able to survive outside their father's mouth provided there aren't predators or strong currents. I like a mesh breeder box for temporary holding and then transferring them to their own vessel/system.

If they are free swimming and not on the bottom of the vessel (their swim bladders are developed) they should be able to eat live foods. Copepods are great, but they should accept newly hatched baby brine shrimp nauplii, which are easy to make on short notice and fairly cheap to have on hand. Cardinals generally go for foods mid water, so when you want to offer something else, pick something that takes a long time to sink but doesn't just stay at the surface - fines of frozen food are good, if trying TDO or similar, maybe B1 size for a first one.

Again, my reference is banggais and I have no experience with this species directly, but once they start spawning, it should be a regular thing. If you're serious about trying to raise them, you should have fairly frequent (monthly or a little longer) spawns, and will be able to make a number of attempts. Mouth brooding fish do some of the parenting themselves in that time holding the eggs and then new fry, so they are comparatively easy to pelagic spawned larvae or eggs, and they shouldn't need as small a food or as obstruction free a tank to survive in because they will likely be able to swim and eat straight out of their parents' mouth.

 

[sabeypets]

I don't know how big they are, but if they are actually like banggai cardinals, they won't need copepod nauplii - the fry will be developed enough out of the mouth that they can eat larger foods - even grown standard copepods - and may start accepting very small prepared foods within a week or two (often early on they need live foods because the movement triggers their feeding response).

If you can catch the male with the eggs when they are about hatching (try and see if someone has a hatch timing available, otherwise it's observation and best guess, and trapping is less stressful than netting) and keep him in a mesh box or separate tank, he should spit them out and start going back to eating in the next day (and offering some food to him can be a way to check if he's got them all out if you can't otherwise tell). If they're like banggais, the fry released may not have their swim bladders fully developed (it depends, I think they normally should), but should be able to survive outside their father's mouth provided there aren't predators or strong currents. I like a mesh breeder box for temporary holding and then transferring them to their own vessel/system.

If they are free swimming and not on the bottom of the vessel (their swim bladders are developed) they should be able to eat live foods. Copepods are great, but they should accept newly hatched baby brine shrimp nauplii, which are easy to make on short notice and fairly cheap to have on hand. Cardinals generally go for foods mid water, so when you want to offer something else, pick something that takes a long time to sink but doesn't just stay at the surface - fines of frozen food are good, if trying TDO or similar, maybe B1 size for a first one.

Again, my reference is banggais and I have no experience with this species directly, but once they start spawning, it should be a regular thing. If you're serious about trying to raise them, you should have fairly frequent (monthly or a little longer) spawns, and will be able to make a number of attempts. Mouth brooding fish do some of the parenting themselves in that time holding the eggs and then new fry, so they are comparatively easy to pelagic spawned larvae or eggs, and they shouldn't need as small a food or as obstruction free a tank to survive in because they will likely be able to swim and eat straight out of their parents' mouth.

"All known species of cardinalfish are mouthbrooders that orally incubate their eggs until hatching 7 to 8 days after fertilization." They are all released upon hatch as pelagic larvae and are challenging to feed due to their small size, with the exception of the Banggai cardinal fish that lacks a pelagic larval phase..

 

[ISpeakForTheSeas]

Yeah, the one I'm familiar with is "Apogon quadrifasciatus" (with the accepted name of Ostorhinchus fasciatus). They were kept at 29C (84.2F) and the eggs hatched after 5 days (I'd imagine at normal temps 7-8 would be about right).

"The average total length of the newly hatched larvae was 2.6mm with an average mouth gape of 160 μm."*

"most marine fish larvae consume prey that are only 20% of their total gape."**

So, assuming these guys are in a similar boat because they're in the same genus, they're likely going to need tiny feeds. As a note here, Bangaii Cardinals, Pterapogon kauderni, are actually in a different genus and - as mentioned above - seem to have different reproductive strategies than the "average" cardinalfish.
*Source:

Breeding and rearing of the two striped cardinalfish, Apogon quadrifasciatus (Cuvier, 1828) in captive condition - PubMed

The present study describes captive breeding, reproductive behavior and larval/juvenile rearing of Apogon quadrifasciatus. Spawning occurred 25 days after stocking in the breeding tank. Clutch size varied from 2500 to 3100. The males incubated the eggs, the incubation period was approximately...

pubmed.ncbi.nlm.nih.gov

**Source:

Spawning, early development and first feeding in the gobiid fish Priolepis nocturna

Spawning, early development and first feeding in the gobiid fish Priolepis nocturna

www.academia.edu

 

[vaguelyreeflike]

An update it seems he’s already released the eggs into the system before I could separate him. Hopefully they spawn again soon and I can attempt again. There are tons of different types of pods in this system so hopefully a baby might make it somewhere but doubtful. I’ll keep an eye out in the sump and stuff lol.

 

[vaguelyreeflike]

Second update, he has another batch! I don’t know if it’s the same male as before or a different one, but we can try again haha!

 

[ISpeakForTheSeas]

Any updates on this?

 

[vaguelyreeflike]

Since the updates, 3 have sold but they still regularly produce, hold, and release eggs into the system. I haven’t managed to catch any as all our breeder boxes allow the larvae to escape and I don’t have a separate system at home for them yet. Once my 9gallon is set up I may buy the rest and take them home to see if I have more success. No babies in the sumps yet haha