breeding bristlenoses

[rfb]

I read an article on this subject and it said that they mistakenly raised the temp to 87 degrees now does this not seem rather warm or is this the trigger that I seem to be missing.I seem to have something missing from what i am doing,I have one pair in a 10 gallon that they seem fine in and feed them good food and they have the bog wood and a pipe with only one entrance.The pipe was one of the things that the local shop insisted would be the thhing that would get them going and it has not.so what would be the next step.

[MatsP]

Bristlenoses are happiest around 24'C or so (75'F). I have read that they will not breed at elevated temperatures, but I haven't tried to prove that myself. I epxect that higher temperature would starve the female of [because higher temp -> higher metabolic rate -> need more food -> no left-over nutrients/energy to produce eggs]. Or maybe it's just the temperature itself that causes them to not spawn, because it doesn't match the temperature when they are genetically programmed to spawn.

30'C is definitiley well above the temperature that you'd want for bristlenose breeding. Drop it to 75'F or perhaps even lower. My first two broods came at 72'F (22'C), later ones at 76-77'F (26'C) [only because I moved some other fish around and had to raise the temperature to keep them happy].

They do need a cave that is suitably large for the male and female to just squeeze into (and you'd be surprised how small a hole they get into if they really want!).

I've found that my male likes to dig his own cave, and when I tried a cave that I thought was great, it didn't work out - eggs came out and got eaten by other fish...

A piece of slate, terracotta saucer or something like that seems to be a favourite for mine.

But each fish is individualy, so some playing about with different things may be necessary.

Big water changes may help trigger, particularly at a lower temperature (simulates rainy season -> breeding season for most plecos).

Feeding some extra protein (blood worms for instance) may also help condition the female.

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Mats

[Dermogenys]

I have one pair in a 10 gallon that they seem fine in

I think that temperature is not that bad 'cause itself but it is the effect that temperature has on air concentration (higher temperature - less oxigen). But more important is that your tank is too small. I once put a proven breeders in a 8 gallon tank with the exactly same water and water conditions as in the tank that they have spawn before. I once read a foollish article that bristlenose male is not gonna spawn unless the tank has in lenght less than 12 times his lenght, but than again, I read a lot of other concerning the tank size and spawning, so the size does metters.

[MatsP]

I agree that the tank may be too small (at least it will be once the fry starts growing, unless they are moved elsewhere). But on the same token, I don't think 12x the length of the male is necessary, as my male has spawned in a 800mm tank, and he's certainly more than 66mm long. More like 80-90mm by now (and last spawn was just a month or two ago).

I also agree that higher temperature will ALSO reduce the dissolved oxygen content in the water, which will adversely affect the fish in many ways, and certainly not promote spawning.

If a single one, or several of these factors, are what's causing your pair to not breed is a good question.

I certainly didn't do anything special to make my pair breed, I just got myself a male to go with the female, and a few weeks later the first fry were swimming about in the tank. Unfortunately, I had a pretty large goldfish in the same tank, which decided that a diet of bristlenose babies was a good one... That was the beginning of multiple tank syndrome...

RFB: what size are your male/female?

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Mats

[Jon]

I would well assume spawning temperature would depend on the species of fish in question. There is no doubt in my mind that, say, L-255 would much prefer conditions of 86F as opposed to the 75F quoted. I have had no difficulty spawning ancistrus of several species in relatively warm tanks.

[rfb]

Thanks to all of you all that info was a great help and I will try to get the temp down and add a sizable water change in and see if that helps before I comandeer my daughters 20 galon tank.As for the size of the hopefull parents they are about 4 inches and I have had them for well over a year so I thought they might be ready.Thanks so much again for all the help

[Dermogenys]

As I said Matsp:

I once read a foollish article that bristlenose male is not gonna spawn unless the tank has in lenght less than 12 times his lenght, but than again, I read a lot of other concerning the tank size and spawning, so the size does metters.

[MatsP]

I would well assume spawning temperature would depend on the species of fish in question. There is no doubt in my mind that, say, L-255 would much prefer conditions of 86F as opposed to the 75F quoted. I have had no difficulty spawning ancistrus of several species in relatively warm tanks.

Good point, I was assuming (rightly or wrongly) that the original poster meant common bristlenose, as in

Ancistrus sp(3)

. Other Ancistrus spp. can and will be both harder to breed and may require more precise and special treatment to make that happen.

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Mats

[Azmeaiel]

what is the youngest bristlenose will spawn? I have a small male+ female (around 7cm each). The male dissappeared for a few days and now I have found him guarding a cave he has dug under a large rock which he wont leave for more than a few seconds at a time. I cannot see if he is guarding eggs and dont want to disturb him if he is. The small female has been very 'fat' latley and eats like a pig. Possible spawn or just a cave-proud male?

[MatsP]

My male wasn't quite 5 cm (TL) when he became a dad the first time. He's a bit bigger now, and four times a father [or around 150 times, if you count each fry].

But I think it will depend a little bit on how they are brought up. Some young ones will grow quite quickly, others more slowly. I've heard someone say that they need to be about a year old to breed. Makes sense to me that it's age rather than (or combined with) size that determines the breeding of the fish.

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Mats

[Azmeaiel]

Thanks for the info. Seems the little guy wasnt joking around. I woke up to find this little guy this morning.

[MatsP]

My guess is that you'll find another 20 or more by the tomorrow evening. It usually takes 2-3 days for all of the fry to come out of hiding.

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Mats

[Azmeaiel]

I think you are right, I managed to squeeze in behind my tank, a quick peek with a torch revealed around 30 more I quickly isolated the only 2 fish in the 60 gal capable of doing the little guys any damage.