Just started trying to breed harlequin rasbora

[yhbae]

The only experience I have so far in breeding fishes are platies so that doesn't count... I picked harlequins since I already have a good mature pair. If I suceed with this, I'll then proceed with panda cories...

Day 0:

- Bought 5.5g. Spent 3 hours building a net that sits about 2 inches off the botton. The net will allow eggs to fall through but too small for the rasboras to go through.
- Added 100w Tronics heater and an air stone. (No filter)
- Filled with water. pH = 7.2. KH = 2. GH = 5. temp = 77F.
- Added two fake (silk) cryptocoryne plants which have broad-leaves. Rasboras are supposed to lay eggs underside of these leaves, but during the first spawning, supposedly most of the eggs fall off to the bottom (hence the net).

Day 1:

- Picked two fishes from the community tank. Male is the dominant one of the pack. Female is the largest and fatest one. (Black patch on their body also confirms their sex).
- Added dechlorinator, and after some debate, added two fishes at the same time. I am supposed to add the female first and condition her but since I feed my community tank so well she is already very fat. Hopefully, they will show some mating behaviours soon.
- Still debating whether to add some peat moss to lower pH or not. According to various articles, some had luck at my pH, others had to go as low as pH 5 to get any results.
- So far, so good. Two fishes appear calm and stays together...

---More to follow---

 

[Inchworm]

Hi yhbae

So, what happened?

I know it's a little late, but I just saw the thread. Hope you had some good luck with them.

 

[mike777]

Yes please update us!! I also have a question.. How can you determine the gender of harlequin rasboras? I have 3 myself and I would like my first fry from one of my fish soon!

 

[yhbae]

Sorry for the late update....

Day 5:

I've been slowly reducing pH over few days now, and the water is at pH of 6.8. I've been doing a large cold(er) water change every two days, and so far nothing! I've read articles where in some cases, they had to really bring pH down to below 6.0. I'll continue to bring pH down slowly...

I've increased the air circulation to the sponge filter to create a bit more current.

Seems weird as the pair seems to be together, almost standing still except during feeding time... Perhaps my pair is still not mature enough? Anyhow, I'll continue for another week or so and see if I can get them to spawn...

 

[yhbae]

Yes please update us!! I also have a question.. How can you determine the gender of harlequin rasboras? I have 3 myself and I would like my first fry from one of my fish soon!

Determining gender of harlequins seem easier than it is for most other species... You can look at the black triangular patch on their side body - if the rear line is near virtical and straight, it's most likely be a female. Male's line tends to curl to some extent. Also, females tend to become more chubby and fat.

 

[Inchworm]

Hi yhbae

It's too bad that you haven't gotten them to spawn yet. But keep working on it; I'm sure you'll succeed.

I was surprised to see that you are trying to breed them one pair at a time. I thought harlequin rasboras spawned in groups with more than one male to each female. Aren't they shoaling fish?

 

[yhbae]

Hi yhbae

It's too bad that you haven't gotten them to spawn yet. But keep working on it; I'm sure you'll succeed.

I was surprised to see that you are trying to breed them one pair at a time. I thought harlequin rasboras spawned in groups with more than one male to each female. Aren't they shoaling fish?

They are shoaling fishes, but from what I have read so far, some breeders pick only one pair for many of the shoaling species - I even read that they try only one breeding pair of cardinals which are clearly shoaling species.

Well, these guys are stubbon, they don't want to mate...

I'll give it few more days and if it doesn't work out, I'll remove the male, condition the female for a wek or two (by feeding her like crazy on live food), then try it again. Hopefully the male will feel "glad" to see the fat uhm I meant more attractive female by then!

 

[Inchworm]

...I'll give it few more days and if it doesn't work out, I'll remove the male, condition the female for a wek or two (by feeding her like crazy on live food), then try it again. Hopefully the male will feel "glad" to see the fat uhm I meant more attractive female by then!

Hi yhbae



Don't you condition the male, too? I would think that he would need to be in top form when the big day comes!

 

[yhbae]

It's probably better to condition both but I want to separate them for a while (that is, if they don't spawn within the next few days). My community tank already gets pretty good selection of food so I figured for the male it might be ok to stay there for a week or two...

What I really need is a tank divider for 5.5g. I already have ones for 33g and 10g but I don't (yet) want to buy another one for 5.5g...

We will see...

 

[yhbae]

Small update:

Well, this experiment kind of ended rather suddenly (in a failure)...

I looked at the tank this morning, and the coffee bag that contains some peat was wearing out in the tank... I was afraid of it eventually breaking, so I put a cup and gently lifted it off..... THEN it went caput! Man, the whole tank became very muddy! I couldn't see any fishes through the glass! I was about to leave so I couldn't do anything. Poor fishes are swiming in mudy water...

Looks like the water has settled down now, but I see lots of peat soils all over the place. I can't even add any water because that creates disturbance to these particles... LOL

I'm gonna take them out, put them back in the community tank, and let them rest before I give them another shot...