Marine Betta

[ThRoewer]

In species of fish that do not display sexual dimorphism, can the gentian check be a reliable way to tell male from female??

In many cases, it can be used. However, it works best with benthic spawners (fish that put their eggs on a surface) and mouth breeders and generally best with larger species.
I tried so far unsuccessfully to find a significant difference with firefish (Nematelotris species).
It may also not work too well with species that can change sex bidirectionally (many gobies, dottybacks, hawkfish,...)

 

[ThRoewer]

What are the other reasons you recommend them small? And what do you consider to be small? I’ve only ever seen 1 at a LFS and it was around 3.5”...possibly 4”.

3 to 4 inches in total size is definitely on the small side.
Reasons to get small ones are:
- smaller ones adapt better to captivity and surrogate foods - my all eat frozen and even flakes ( though with flakes they are at times picky about the brand and type).
- smaller ones (below 4" total length) should still be females.
- you will have them longer as they are usually no older than 3 years (life expectancy is 20 to 30 years or even more). With adults, it is not easy to tell how old they are.
- individuals you got small are less likely to eat the cleaner shrimp you have with them in the tank (assuming you feed them enough. A starved Marine Betta may eat any shrimp it can find).

 

[Han]

That’s awesome, have you ever considered breeding other species of roundheads? I would imagine it would be a similar process, but as far as I know the marine betta is the only one to have been captive bred. Which is a shame because there are a lot of beautiful roundheads.

 

[TriggerFinger]

Thanks again. I was really intrigued by the betta at the store but it had tattered fins and looked a little too thin. I wasn’t in the position then to nurse a sickly fish back to health so I passed. I ended up with a starry blenny as they have a similar pattern and it turned out that I love him. This is really cool, I hope your able to get some babies raised!! If you get to that point, I would love to be added to a waiting list if you decide to sell and ship them to hobbyists. Good luck!
here’s my pretend marine betta, his name is comet

 

[vetteguy53081]

Way to go

 

[ThRoewer]

That’s awesome, have you ever considered breeding other species of roundheads? I would imagine it would be a similar process, but as far as I know the marine betta is the only one to have been captive bred. Which is a shame because there are a lot of beautiful roundheads.

I had planned to get more serious with breeding Assessors but lost one of the pair of Yellows I had in a power outage. And with my randalli I don't know if they are a pair yet.
I had found a nest of the Yellow assessors but didn't have a suitable tank ready and just a little bit of Tisbe as food:



I also have a trio of Bluespot Jawfish in their own species tank but I'm not yet entirely sure if there is a male among them. In the past I had a pair that spawned at least once:


The issue with my current ones right now is that they are still in their QT which is a bit obstructed by other QTs and therefore also a bit neglected:


I have a 75-gallon Aqueon tank for them but have to build a rack to put it in first. I'm gonna make a thread about them in the future

 

[hmmmmm]

Great info! Honestly did not know they could be tank bred. I had one in a previous tank and it looked incredible, bit too shy unfortunately so always had to look for it for 2 days.. I have one on my fish list for my next build ;Happy If you have a pair, will they swim together?

 

[ThRoewer]

Great info! Honestly did not know they could be tank bred.

Marine Bettas are one of the "older" fish to be tank-bred. The issue is that it takes 6 months to a year or even more to get them to a sellable size which is a lot of commitment and cost. C-Quest, Sustainable Aquatics, ORA, and I think also Sea&Reef all bred them for a time but stopped because they couldn't get the money for them it cost them to raise them.

The Dutch aquarist Herman Wassink was the first to breed them in 1986 or 1987 and published it first in 1988 in the German Aquarium and Terrarium magazine DATZ.
To my knowledge, I was the second to breed them successfully in captivity in 1992.
But I was likely the first to "build" pairs for breeding purposes by picking males and females and putting them together. Wassink just got lucky to find a pair and didn't know which of them was the male and the female.

I had one in a previous tank and it looked incredible, bit too shy unfortunately so always had to look for it for 2 days.. I have one on my fish list for my next build ;Happy

For some, they are reclusive as singles. I never had that issue (never had a big enough tank to "lose" a fish in). Much has to do with the tank mates and the appropriate rockwork with plenty of caves with large entries. My Marine Bettas usually like to stand in the entry of their cave.

I also noticed that captive-bred and small wild-caught specimen will be more outgoing, even as fully grown adults. Another reason why small individuals should be preferred.

If you have a pair, will they swim together?

No, they do not form close "mated" pairs like anemonefish, butterflies, angels, gobies, and the like. They usually only come together to spawn and once done, the female is chased out of the male's cave and not allowed back in until the eggs are hatched.
I suspect they form harem groups in the wild.
What you will get with two (or more) is a lot more visibility of the fish and far more interesting behavior.

 

[Zionas]

What do you feel is the best size to get them? I am aiming for 6-10cm. I remember you said the best way to pair them up is to get a small individual about 6-7cm and another 8-10cm? What are the chances of success if I go that route?

 

[Hugh Mann]

This is my Betta, I absolutely love this fish, my favourite besides my moray. Still a bit on the small size, maybe 4" or so nose to tail. From your write up, she'll be female for a while longer?

I would love to eventually get a second one when I upgrade to a larger tank, but have read it can be somewhat difficult, but you just made it seem pretty easy to get them to coexist.

 

[ThRoewer]

What do you feel is the best size to get them? I am aiming for 6-10cm. I remember you said the best way to pair them up is to get a small individual about 6-7cm and another 8-10cm? What are the chances of success if I go that route?

I would think pretty good. That's about how both of my current pairs started out.

 

[ThRoewer]

This is my Betta, I absolutely love this fish, my favourite besides my moray. Still a bit on the small size, maybe 4" or so nose to tail. From your write up, she'll be female for a while longer?

I would love to eventually get a second one when I upgrade to a larger tank, but have read it can be somewhat difficult, but you just made it seem pretty easy to get them to coexist.

Yep, looks like a female.
How big is your current tank and what other fish do you have in there?
I found that pairing them is fairly easy. In my experience, females get along fairly well and if you have a male it looks like it will readily accept a newly added female. With two females there will be a bit chasing to assert dominance by the larger one so she can become a he. Males usually only get (mildly) aggressive against females when they are not ready to spawn or get to close to a nest.

 

[ThRoewer]

The male of my first pair - now harem group - had eggs when I checked on them this evening. The eggs are the beige mass on the roof of the cave he tries to hide with his dorsal fin:



From the size of the egg-ball, the newly added female must have laid them. She was only added 9 days ago which is a new record on my book.

Now I need to get cracking to finish the larva tank...

 

[Hugh Mann]

Yep, looks like a female.
How big is your current tank and what other fish do you have in there?
I found that pairing them is fairly easy. In my experience, females get along fairly well and if you have a male it looks like it will readily accept a newly added female. With two females there will be a bit chasing to assert dominance by the larger one so she can become a he. Males usually only get (mildly) aggressive against females when they are not ready to spawn or get to close to a nest.

Currently a 55, housed with a flame hawkfish and cleaner wrasse. There used to be more, but Velvet killed most everything else. Got a small moray that was in the tank, but sitting alone in a separate system due to copper sensitivity. Plans to eventually upgrade to a 210 gallon.

Seems pretty simple enough, I had heard horror stories of bettas severely injuring or even killing one another. Biggest problem might be finding a healthy and appropriately sized Betta. I've seen 3 in 4 months, and only mine was healthy, the other two had swim bladder issues.

 

[Zionas]

Are swim bladder issues common for these guys? Are they among the species more commonly collected using cyanide? Or do you think it was more due to the long travel distances from Southeast Asia to Europe?

 

[ThRoewer]

In this video, the eggs can be seen better:

 

[Hugh Mann]

Are swim bladder issues common for these guys? Are they among the species more commonly collected using cyanide? Or do you think it was more due to the long travel distances from Southeast Asia to Europe?

At least at my lfs, they say it's common enough that some of the employees said they should stop importing them. They also say it's typically due to being captured by inexperienced divers that rise too quickly as they're a deeper water fish.

 

[TriggerFinger]

Are these the eggs circled in blue?

 

[ThRoewer]

Are these the eggs circled in blue?

Yes.

 

[ThRoewer]

A video of hundreds, if not thousands, baby Marine Bettas at Sustainable Aquatics: