Breeding common bristlenose

[cprize]

Hi all, i used to breed common bristlenose a while ago and going to get back into it soon.

My questions are, what triggers them to breed? I never did water changes etc to stimulate breeding, although i had some nice tight caves for them to hide in.

Also how many adults could be housed in a 4ft or 6ft tank? Im planning on getting 10+ adults.

What is the size of an average spawn from an average sized female? And how often do they breed?

[MatsP]

Most of the time, they don't need a trigger as such. Sometimes a water change with cooler water will start them off, but if they are kept in good conditions, they will just breed and breed and breed.

As to how many you can keep in a 4ft tank - depends on how much water you change each week and such, but 10 adults is certainly possible. However, if you are breeding them to sell, I would recommend a male and two females per tank. More males, and the males may end up fighting over territory/females more than they are interested in breeding. And having more fish just means that the fry has to be moved out of the tank sooner - if you have a 4-6ft x 2ft base and 18" tall, you could probably keep the fry in there until they are ready to sell (around 1" total length), based on one male and two females, although the babies will grow quicker if you constantly remove the largest ones to another tank.

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Mats

[cprize]

I see, yeah i didnt do much with my Bristlenose they bred unexpectedly, and many times.

So if i had a 4ft tank and wanted to breed would i only be able to keep the 1 male to two females? I was hoping to get a large tank, so i could have say, 4 males, 6 females.

Do bristlenose eat their fry? Mine didnt, i was hoping to rear everything in the one tank, or i could have a spare 3ft just for the fry once theyre about 2cm?

Also how often and how big are they spawns? I was averaging 30-50..and mine were breeding monthly.

Thanks

[MatsP]

I see, yeah i didnt do much with my Bristlenose they bred unexpectedly, and many times.

So if i had a 4ft tank and wanted to breed would i only be able to keep the 1 male to two females? I was hoping to get a large tank, so i could have say, 4 males, 6 females.

Why? Having more males and females will just increase the speed at which you reach the level of saturation in the local market - or do you have a way of getting rid of several hundred fry every month, for many months/years? I reached local saturation quite soon after I started breeding my one pair - there is only so many fry you can deliver to a local shop each month. Or are you breeding them for some other purpose? And if you do have that many breeding males, you will have to move the fry on before they can be sold, that's for sure.

Do bristlenose eat their fry? Mine didnt, i was hoping to rear everything in the one tank, or i could have a spare 3ft just for the fry once theyre about 2cm?

No, the parents (or other adults) do not eat fry.

Also how often and how big are they spawns? I was averaging 30-50..and mine were breeding monthly.

Thanks

Every 4-5 weeks - they may take a break if the water gets too warm or too cool, but if you keep the conditions right, they will probably breed for at least 10 months of the year, and 30-80 depending on size/age of the female (and probably amount of food, clean water, etc). And if you look after them well, you should get most of these to saleable size - yields of over 75% can be achieved without too much difficulty, just regular 40-50% water changes every 2-3 days, and plenty of food.

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Mats

[cprize]

There is a big demand in common bristlenose where im from, they sell quickly and LFS are always taking them.

Also friends etc will definately have them, if not, i have the room and time to keep more haha

So a 4ft tank will be enough for a 4 males 8 females lets say? with many hiding spots and caves etc.

Monthly they should turn over im guessing 500+ fry? I have bred them before and theyre easy to keep and the fry wernt hard to raise, i just wanted what spawn size, tank size with amount of adults. If a 4ft is enough for them to live and breed happily, then ill get into it in the near future..

Thanks!

[MatsP]

I'm not sure if you are realistically thinking that you can churn out 500 fry a month for "ever", but I think you need to consider that there are only so many fish-tanks, and once there is one or two bristlenoses in the tank, you don't have a customer there until that one dies, and if the fishkeeper is half-decent, that's 5-10 years. In a large city, say Melbourne, the population is 4 million. and there is probably about 2 million households in a 4 million population city. On average, I'd say there is one freshwater tropical fishtank per 10-20 households - say 7% of the households (1 per 14.1 households), so that makes 140000 tanks in Melbourne. Not ALL of those want a bristlenose (they either have one, or a common pleco, or something like that). There are probably at least 10 fish-shops in a city that size, and some of those will not want to upset their regular supplier of bristlenoses. Let's say you distribute your fish amongst 4 shops that you are "friends with". That means 40% of 140000 potential customers: 56000. That is 112 months worth of fish, or about 9 years. Have you got agreement with any shop right now that they will take upwards of 100 fish per month from you, every month?

But I think that is a very optimistic calculation.

And you need several large tanks for the fry to be growing out in: do you have 4-5 tanks large enough to hold the fry?

I would start small and see how it goes. If it goes well, then you can expand your business, but bear in mind that eventually, every possible place where you can give a home to a bristlenose _WILL_ be filled.

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Mats

[cprize]

Lol yeah i understand what youre saying, i just threw a number out there, since they are prolific breeders..

With a colony of 12, in a 4ft will i house them properly? Including the proper conditions etc.

Thanks.

[MatsP]

I still don't understand why you want to keep many adults in the same tank... If you keep more than one male in a tank, it's quite possible that the multiple males will "argue" about who's got the right to mate with the female(s), and if you have several large tanks, I'd rather keep one pair/trio per tank, and leave the fry in the breeding tank - saves the effort of trying to catch the little fry when they are only a week or so old - much easier to catch them a couple of months old when they are a bit bigger and not so small/fragile.

If you don't have many large tanks, you have nowhere to keep the fry anyways, so it's just a waste to keep many adults in one tank.

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Mats

[cprize]

That was one of my questions whether or not it was ok to keep them all in a 4ft tank?

If not what would you say would be a good number of adults, and sex ratio for a 4ft tank?

[MatsP]

That was one of my questions whether or not it was ok to keep them all in a 4ft tank?

If not what would you say would be a good number of adults, and sex ratio for a 4ft tank?

"Ok" (they won't kill each other) and "recommended" (will produce regular, good size batches of fry) are two different things, and it's not a question of the size of the tank [1] - if you have more than one mature male in a tank, the males will interfere with each other. But assuming they don't, I still don't see the point in going directly to "industrial level reproduction".

I recommend one male and two females, like I said in the first or second of my replies.

[1] unless we're talking really HUGE, swimming pool size tanks - but certainly anything less than 8ft or so, the two males will KNOW that the other is there.

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Mats

[cprize]

Thanks, i will probably get a 3ft and chuck a trio in there, sound reasonable?

Also with too many females the male will start kicking eggs out wont he? lol

[MatsP]

I don't think the male will kick out the eggs, but he'll be exhausted if you put more than two females in there, because he'll never be able to go feed.

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Mats

[Barbie]

A couple notes to add here:

I had a spawn of 204 fry from a tank with two females and one male bristlenose. I had read reports of huge spawns like that and always thought people exaggerated, until I actually counted the little monsters. The spawn did not look inordinately large, so I would assume one trio was cranking out those fry indefinitely.

My male Ancistrus regularly leave their caves and feed when I drop in their dinner. I keep my spawning tanks as species tanks though, so they aren't worried so much that something will rush in and attack their children. I also have had spawns at 3 different developments in a cave with a male. Don't count on them self limiting the number of fry.

I am known in the area for rare plecos and I sell an average of 120 plecos a month. The shop has no employees, just me as head cook and bottle washer, but I doubt a single shop is going to be able to move more than that, without a very large clientele. Start with a couple trios and in 6 months you'll wonder how the heck you thought you could get rid of all the fry. I know it's tempting to go big or go home, but trust us, it gets out of hand in a hurry!

Barbie