Betta Bubble Nest

Breeding Bettas, Siamese Fighting Fish, Part 9 – The Betta Bubble Nest

Since I’ve now managed to get my second Siamese Fighting Fish spawn to the free swimming stage I’m still far from being an expert but there was a few things that I have noticed about the Betta Bubble Nest that I thought would be worth mentioning especially since they were things I hadn’t come across elsewhere in my research.

Firstly though, the Betta Bubble Nest is where the tiny Bettas eggs are stored until they hatch and then afterward the fry will live off their yolk sacs for a few days until they can then swim away from the nest. It is made and maintained by the male Betta until the fry are ready to leave the nest.

Therefore if you do your research on this topic you will discover that most breeders use half a Styrofoam cup that has been cut along its length as it should easily float on the surface of the water. They also use a piece of tape to secure it to the side of the tank so it doesn’t float away. What I discovered in my first spawn though was the cup just seemed to stay where I left it as I had my filter turned on ever so slightly and the small amount of surface current just seemed to keep it in the opposite corner.

During my second spawn though I’d tried the same method but discovered that for some reason my cup slowly started to sink (despite coming from the same packaging) over a period of a few days. Not much though, only about a few millimetres, but enough to put some doubt in my mind as to how it would last once the male started to make his bubble nest in it.

So the solution was obvious, it had to be secured. Now most breeders just use some tape and secure it to the side of the breeding tank but I had a couple of problems with this idea. Now I’m not going to tell you not to use tape but I will explain my reasoning and then it’s up to you to decided.

Firstly, tape obviously has some sort of chemical in the adhesive and despite the tape being above the water line there is still quite a bit of condensation on the inside of the tank wall (see the photo). So there is some chance that some of this residue will end up in the water. Now that fact that some breeders use it suggests that this isn’t a problem but then again not all tape is the same everywhere so who’s to say just because it worked for the majority that the minority won’t have a problem with it.

After all when you read the trouble some breeders go to, to maintain water quality (and rightly so, water quality is very important) and then introduce tape to the water it makes you wonder? After all when the tape is removed it will leave some residue behind and despite it being above the water line at the start, the water level will rise as you add water later as the fry get larger. You can bet then that some of that adhesive residue that was left behind will then get absorbed into the water. So maybe I’m pedantic but I’ll leave it up to you to decided. Enough said.

Styrofoam Cup or Bubble Nest

I used string to suspend both ends of the cup to stop it from slowly sinking and then taped the string to the outside of the breeding tank.

Therefore instead of using tape I used string, threaded it through the gap between the two pieces of glass used for the lid/cover and then taped it to the outside of the breeding tank. This also enabled me to secure both ends of the cup to keep it balanced so it wouldn’t sink.

The next thing I discovered during my second spawn was the male Betta was having a bit of trouble keeping all the eggs in the bubble nest. One or two would fall out so he’d go and retrieve them from the bottom and when he’d place them back in the nest he’d dislodge more eggs and so the cycle would go on and on, it was a case of……..put some back and then knock some more out. This makes for a lot of work for Mr Betta.

Now during my first spawn the male Betta didn’t have this problem at all but the second spawn had two or three times the amount of eggs the first one had. This led me to conclude that the bubble nest in my second spawn was very cramped for space as it spilled over the edges of the cup.

Therefore the next time I breed Siamese Fighting Fish I think I’ll place both the halves of the cup together so if the male needs more space, he’ll have it. Now having said that though, I’m sure that in most cases the male will just extend the bubble nest on the outside of the cup if he needs to but this male didn’t so maybe in hindsight the extra cup side by side may have encouraged a larger nest. Who knows? but if it makes less work for the male then it’s worth it.

The next thing about bubble nests I’ve discovered is, if you’re new (or even experienced) it might be best to place the Styrofoam cup on the side of the tank closest to where you can view it and the reason why is this. If you can view it clearly you can keep an eye on how things are progressing.

Now during my second spawn I did this initially and the male Betta seemed reluctant to build his nest in it so I concluded he wasn’t happy with the position and wanted a bit more privacy. Therefore I added the other half of the cup just around the corner where I could still see it but was slightly more private. He then had two choices for his nest but amazingly when he did build his bubble nest he chose the first cup so in the end I suppose privacy really wasn’t the issue and he was just taking his time. As it turned out though he did use part of the second cup as there was a small bubble nest there as well that I noticed had fry dangling from the bottom.

Therefore as I said before, I think it’s best to add both halves of the cup side by side and then let the male decide from there. As far as privacy goes it didn’t seem to be an issue. At the end of the day the male will decide where he wants to build his bubble nest so if he doesn’t like where you’ve placed the cup he may just go and make it somewhere else anyway, without a cup.

Therefore encouraging the male Betta to make his bubble nest where you can see it clearly has several advantages for a new breeder. As you’ll find when you research this topic on the internet most experienced breeders will tell you the eggs will hatch between 1 to 3 days after spawning. Now I took this to mean that they will all hatch at about the same time within this time frame and it wasn’t until my second spawn that I discovered this wasn’t quite the case. You see, during my first spawn the bubble nest was on the other side of the tank and my lighting wasn’t as good as it could have been so the fry weren’t as easy to see.

For my second spawn, because I’d placed the cup where I could see it more clearly I noticed that the fry don’t all hatch at the same time. Some of the eggs hatched after one day and then the rest continued hatching up until the end of the second day (in this case). So what I found was that some fry that hatched early got a head start eating their yolk sac and then some even preceded to leave the bubble nest while the others were still hatching.

Now some of these were retrieved by the male Betta and placed back in the bubble nest but I’m sure there were quite a few that weren’t as he was very busy retrieving falling fry as well.

So what I found was that some fry were at the “free swimming” stage (this is where they can swim horizontally away from the nest) while others had just hatched. This then presents you with the problem of deciding when to start feeding your Betta fry. Now I tried to research if “free swimming” meant the yolk sac was all eaten but couldn’t find a definitive answer so I just decided that once they’d left the nest it was time to start feeding them. You see if you don’t feed them straight away they can get weak and then lose the ability to find food and then die. Having said that though if you do decide to add Java Moss to your breeding tank, I’m led to believe it will add some Infusoria to the water so any “early developers” will have some food to sustain them for a while if you’re slow to feed them.

Therefore what I found was for a day I was feeding free swimming fry while the male Betta was still tending to the rest of the fry in the bubble nest. Then on day three after the first fry started to hatch I discovered that the male Betta was catching free swimming fry and placing them back in the nest. There was still a few fry that appeared to still be reliant on the nest, but it was then I decided it was time to remove the male as most of the fry had left the nest or were continually trying to and getting put back in.

Just a few hours after Dads removal the bubble nest was empty and the fry were all free swimming. How many I had at this stage I wasn’t sure but they were quite a bit easier to see than the fry in the first spawn as they were noticeably larger.

So you can see how important it is to have a clear view of the bubble nest so you can keep an eye of how things are going. That way you can then judge when to start feeding the fry and when it’s time to remove the male.

The other thing to take into account is the importance of keeping the area below the bubble nest clear of any Java Moss. If you decide to place Java Moss in your Betta breeding tank make sure it’s up the other end (this is another advantage of a larger tank) as eggs will fall to the bottom during spawning as well as during their time in the bubble nest. Also once the fry hatch they will also fall from the bubble nest, sometimes to the bottom, and they will have to be retrieved by the male Betta as well.

Another point worth mentioning is the fact that you will have to leave a light on 24 hours a day for the entire time the male Betta is tending to the bubble nest so he can maintain it correctly. You will also find that in a large spawn as this one was that the male will be very busy and will make many, many trip to the bottom of the tank and back.

Therefore I’ve concluded that the next time I breed Bettas I might limit the water depth to just 10 cm. The recommended depth is 10 to 15 cm and I used 15cm on both occasions but I feel that by making it just 10 cm you can reduce the workload for the male Betta quite considerably.

In the video above you can see the dark lines in the bubble nest which are fry hanging down. Occasionally you will see one or two drop from the bottom and then swimming back up again. Some will also fall and have to retrieved by Dad. You might also notice Dad knocks some free while replacing others. The amount of fry hanging from the bottom gradually seemed to increase over a 12 hour period as they hatched (despite some leaving the bubble nest) and then decreased again as they started to swim free. This bubble nest was full of a lot of eggs and fry and didn’t really seem quite large enough. Dad was kept very busy replacing eggs and fry for about 3 days after spawning.

Another item you may find helpful for checking the bubble nest is a magnifying glass. The fry are very small and although visible you may find any type of magnification helpful. Another method I tried to use to get a better view of the fry was my camera. Unfortunately, it didn’t have a manual focus and the auto focus kept focusing on the side of the tank rather than the subject, the fry. You many have already noticed this from the video above.

So these are the basics about bubble nests and what I’ve learnt so far from my two spawns. As I’ve tried to display, both my spawns were different so there will be a very good chance that your’s will be different as well. Therefore the biggest lesson I’ve learnt so far is to do as much research as possible and not to expect things will go exactly how someone else has described it in a book or on internet site.

If you read only one person’s version of how the very inexact science of breeding Bettas is meant to go then there is a very good chance that you will be left scratching your head and wondering why “this didn’t happen” or “why something happened you weren’t expecting”.

Breeding Bettas, Siamese Fighting Fish, Part 10 – Removing and Caring for the Male Betta

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