Mt ottos are spawing like crazy!

[peterl]

This is my first post in this forum, but I am a regular contributor in another fish forum.

I have four adult otocinculus in a 15 gallon tank with a lot (~300 or more) cherry shrimp. I am not sure of the species, but based on the pictures in the cat-elog they look like huaorani. Can anyone verify the species?

They have been spawning just about weekly for the last 8-12 weeks. I never see mating bahavior, nor do I see eggs, but every week there are new fry. I just noticed at least 6 today that are about 1/4 inch long. I also noticed the female is full of eggs again.

The tank is fairly heavily planted with EcoComplete for the substrate. Filteration is from an AquaClear 150 with two sponges and a sponge prefilter on the intake. Water parameters are:

pH 6
Ammonia (ppm) 0
Nitrite (ppm) 0
Nitrate (ppm) <5
KH (°dKH) 1
KH (ppm) 17.9

I feed the tank Omega One veggie flakes in the morning, and crushed Omega One veggie rounds in the evening. A couple of times a week they get crushed shrimp pellets, too. I also feed them either cucumber, zucchini, or peeled lima beans once a week.

I do 30-40% water changes each week. I squeeze the muck out of the Aquaclear filter sponges once a month or so.

When I add fresh water, I make sure it is a few degrees cooler than the tank. I started doing this a couple of months ago. maybe that is what triggered spawning. My Sterbai corys have spawned three times in the last two weeks, too.

Here are some pictures.

Peter

[pLaurent1251]

Wow, congratulations on the fry!! Whatever you're doing, they sure like it!

[andywoolloo]

looks fantastic!!

That's so funny cause for the first time the other morning I saw my otos in my 20 long spawning all over! It was so cool!!! They were chasing each other like my cories do and then twisting all around each other like worms!!

[Birger Amundsen]

Very nice, congrats

[Mike_Noren]

Congratulations, otos are NOT easily bred fish, so you should be rightly proud of your achievement!

As for the trigger: both water changes and the presence of spawning Corydoras have been reported as triggers for Otocinclus of the vittatus-group.
One guy reported that he only had spawning Corydoras in the tank for the first breeding, and that the otos continued to breed without other stimulus than water changes after that, much like yours apparently do?

[apistomaster]

I second Mike's comments. I haven't been able to spawn any otocinclus spp yet although I have seen them go through the motions. My group is dwindling down from 12 to 4 after about 4 years so i need to get another group and maybe they will do as Andy wolloo.

I did find a single fry from this species of Parotocinclus but never got any more and now i don't have enough to spawn. I find these mixed in with Parotocinclus jumbo shipments occasionally. They are called Microlepidogaster notata in vol 2 Aquarium Atlas, Baensch although I know that name is invalid. Like the text in that book describes, apparent females fill to almost bursting then loss the weight temporarily but never are any eggs to be fond. This is a photo of my Parotocinclus spp.

maybe some of these are egg hiders and just stick them here and there among the plants. Setting up a dedicated tank would be the better way to try to spawn any of the Otos or with a dwarf Corydoras which would spawn and perhaps stimulate the Otos into spawning but not present a threat to any Otocinclus eggs like large spp such as C. sterbai which are quick to eat eggs and even defenseless fry.
Learning how to predictably breed the Otos and Parotos would be good since there are some very attractive species like Zebra Otos or even my gold Flaked one that would be a thrill to raise tankfuls of. Heck, any group of home grown Otcinclus would be a cool accomplishment.

[nvcichlids]

I had pretty much the same experience with otos and corys breeding. My otos (were 4) just started to wiggle and stick around eachother alot more. I had 3 fry that were all eaten, and now I am with just a pair.

Apistomaster, I have that exact type of paraoto in my tank. Mine is a female, she needs a male. (see avatar)

[apistomaster]

I would like a dozen Parotocinclus spilosoma and set them up with my breeding Corydoras hastaus. I think I am down to only females and they are getting old.
Breeding Otocinclus would please me as much as many much rare Loricaridids. It is solving the puzzle it takes to breed a given species that makes
this such a fascinating hobby. I hope your fry survive and that many more are forthcoming.

[andywoolloo]

that's a beautiful fish, Parotocinclus spp. Nice picture also.

[nvcichlids]

gah! LFS has the paraotos for 9.99 or 3/25.. don't know if I would want them or the cent. perugiaes instead...

[peterl]

The fry keep showing up!

My question now is how many can I house in my 15 gallon tank? At what size can I start moving them into my 3 ft. cory tank?

TIA

Peter

[apistomaster]

The fry keep showing up!

My question now is how many can I house in my 15 gallon tank? At what size can I start moving them into my 3 ft. cory tank?

TIA

Peter

Hi Peter,
More kudos for you!.
My general rule is if I have to ask myself if the fry are ready to move then they probably aren't ready. I look for them to be completely metamorphized from larvae to miniatures of the adults and that they have become easily fed on the same foods as the adults. Not a very well defined point but it is a judgment call in the end.
I think 30 fry would be a safe number to accomplish most of the grow out and then revisit the stocking levels if they appear too crowded.
I like to use a HOB power filter with an effective pre-filter, an air stone and a sponge filter driven by a power head. I would use an equvilant power head to the Maxi Jet 400 for a 15 gal tank. This arrangement simulates the flow of a small stream fairly well and assures the O2 is near or at saturation for the temperature of the water. The prefilter and sponge filter also helps concentrate foods where they are easily grazed on by the young Otocinclus. This is a system that parallels the type I use for raising Corydorad hastatus scaled down slightly for a 15 gal. I use a 20 long and can support well over 100 fry plus the 10-20 adult breeders. So I think my recommendations errs on the conservative side.
Today I finally divided my C. hastatus between the 20 long and a 36 X 13 X 18 inch , 35 gallon tank and am growing out about 30 SA Annual Killies, Simpsonichthys constansciae. The Killie reach spawning size in 8-10 weeks post-hatch and are transient inhabitants. The 35 will become a second production tank for the C. hastatus. They are easily raised in a permanent set up and I harvest it for sales to keep the numbers from going too high and causing a population crash. I have been wanting to divide my "eggs' between 2 baskets in case of a unexpected catastrophe.
I plan to use this approach for my first serious attempt to breed and raise some Otocinclus. The two species share quite a few similarities. One of which is that spawning seems much easier if the breeding population is fairly large.