Breeding rosy loaches
Posted: Tue Aug 27, 2013 10:11 am
Hi all,
Seeing as so few loaches seem to be breedable in the hobby, I thought I'd post a quick account of one very easy to spawn species; the rosy loach, Petruichthys sp. 'Rosy' (previously Yunnanilus sp. 'Rosy' and often ficticiously named "Tuberoschistura arakanensis".
There are one or two previous references to breeding this loach already in aquaria, but they can be a little tricky to track down and somewhat confusing, but in essence they are like any other egg-scattering fish...
Keeping them
Keeping the adult rosy loach is straightforward. They seem to prefer being in groups of 10 or more - less than this and they can be very shy. They don't shoal often (sometimes after water changes), but tend to chase each other around in groups of 2 or 3. They will also follow other fish, and even shrimp. In my experience females are shyer and less active than males. They appreciate plants and other cover in which to hide, but are very active in mid-water - I keep mine in a 90x30x90cm tank and wouldn't recommend anything less than a 60cm tank, despite their small size (about 3cm fully grown). They are unfussy eaters and will eat almost anything I add to the tank. Small live foods are definitely recommended for getting them into breeding condition.
I keep mine in cool (20-24 degrees), medium-hard water (140-240ppm) with a pH that ranges between 7.2-7.8, tankmates include D. erythromicorn, Sawbwa resplendens and T. ocellicauda.
The display tank where mine live -
Adult males resting in the plants -
And you can see a video here of the adults in the display tank -
http://vimeo.com/72537889
Sexing
There seems to be some confusion over this in the online profiles. Sexing mature fish is very easy; females are completely grey and speckled, adult males vary between yellow, orange and a deep pinkish red depending on age and breeding status and may have a single dark lateral stripe, or a mixture of stripe and dorsal freckles. If a fish shows any colour, it's a male. Juveniles of both sexes are grey and speckled and hard to differentiate. Adult females are also deeper bodied with a slightly hunched appearance.
Breeding setup
I had seen spawning behaviour several times in the display tank, but eggs/fry were inevitably eaten by the other occupants, so I moved a trio (1M:2F) of loaches to a 25l breeding tank with a mesh bottom to protect the eggs, heavily overgrown with ferns, mosses and floating plants and filled with aged water from the display tank. Water stats were 22 degrees, 215ppm, ph 7.4, and the tank was full of cyclops and other microorganisms for fry to feed on and also contained a few shrimp and snails.
Breeding tank (mesh bottom not shown)
I fed them plenty of live daphnia and mosquito larvae and after 2 days they settled in and I witnessed several bouts of spawning behaviour (the males vigorously chase the female, eventually cornering her where they assume something of a 'T' position, but with lots of twisting around). This continues for a number of minutes until the female is spent. The eggs seem to be scattered at random amongst plants but I never saw any directly and I was unable to determine if they were adhesive or not. 2 days later I spotted the first tiny fry at the bottom of the tank and so removed the adults.
Fry growth
I ended up with 10 fry from the two females (not sure if one or both spawned), form an unknown number of eggs. The fry grow quite quickly and I did not notice any mortality. For the first week I fed them nothing - they fed happily on rotifers, baby cyclops and whatever else was growing in the tank. After a while I started them on microworm and then small sized 'golden pearls', both of which were accepted eagerly. The fry quickly become very active and move from being largely benthic to exploring the whole water column within about a week. By day 50 they measure about 1cm TL and were large enough to add back into the display tank, where they seem to be doing fine.
Fry at about 2 days old -
7 days old -
12 days old -
24 days old -
53 days old, before moving to display tank -
Video of juveniles feeding at around day 50 -
http://vimeo.com/72547098
So there you go, really easy egg-scattering loaches, and beautiful fish to boot. Highly recommended.
Seeing as so few loaches seem to be breedable in the hobby, I thought I'd post a quick account of one very easy to spawn species; the rosy loach, Petruichthys sp. 'Rosy' (previously Yunnanilus sp. 'Rosy' and often ficticiously named "Tuberoschistura arakanensis".
There are one or two previous references to breeding this loach already in aquaria, but they can be a little tricky to track down and somewhat confusing, but in essence they are like any other egg-scattering fish...
Keeping them
Keeping the adult rosy loach is straightforward. They seem to prefer being in groups of 10 or more - less than this and they can be very shy. They don't shoal often (sometimes after water changes), but tend to chase each other around in groups of 2 or 3. They will also follow other fish, and even shrimp. In my experience females are shyer and less active than males. They appreciate plants and other cover in which to hide, but are very active in mid-water - I keep mine in a 90x30x90cm tank and wouldn't recommend anything less than a 60cm tank, despite their small size (about 3cm fully grown). They are unfussy eaters and will eat almost anything I add to the tank. Small live foods are definitely recommended for getting them into breeding condition.
I keep mine in cool (20-24 degrees), medium-hard water (140-240ppm) with a pH that ranges between 7.2-7.8, tankmates include D. erythromicorn, Sawbwa resplendens and T. ocellicauda.
The display tank where mine live -
Adult males resting in the plants -
And you can see a video here of the adults in the display tank -
http://vimeo.com/72537889
Sexing
There seems to be some confusion over this in the online profiles. Sexing mature fish is very easy; females are completely grey and speckled, adult males vary between yellow, orange and a deep pinkish red depending on age and breeding status and may have a single dark lateral stripe, or a mixture of stripe and dorsal freckles. If a fish shows any colour, it's a male. Juveniles of both sexes are grey and speckled and hard to differentiate. Adult females are also deeper bodied with a slightly hunched appearance.
Breeding setup
I had seen spawning behaviour several times in the display tank, but eggs/fry were inevitably eaten by the other occupants, so I moved a trio (1M:2F) of loaches to a 25l breeding tank with a mesh bottom to protect the eggs, heavily overgrown with ferns, mosses and floating plants and filled with aged water from the display tank. Water stats were 22 degrees, 215ppm, ph 7.4, and the tank was full of cyclops and other microorganisms for fry to feed on and also contained a few shrimp and snails.
Breeding tank (mesh bottom not shown)
I fed them plenty of live daphnia and mosquito larvae and after 2 days they settled in and I witnessed several bouts of spawning behaviour (the males vigorously chase the female, eventually cornering her where they assume something of a 'T' position, but with lots of twisting around). This continues for a number of minutes until the female is spent. The eggs seem to be scattered at random amongst plants but I never saw any directly and I was unable to determine if they were adhesive or not. 2 days later I spotted the first tiny fry at the bottom of the tank and so removed the adults.
Fry growth
I ended up with 10 fry from the two females (not sure if one or both spawned), form an unknown number of eggs. The fry grow quite quickly and I did not notice any mortality. For the first week I fed them nothing - they fed happily on rotifers, baby cyclops and whatever else was growing in the tank. After a while I started them on microworm and then small sized 'golden pearls', both of which were accepted eagerly. The fry quickly become very active and move from being largely benthic to exploring the whole water column within about a week. By day 50 they measure about 1cm TL and were large enough to add back into the display tank, where they seem to be doing fine.
Fry at about 2 days old -
7 days old -
12 days old -
24 days old -
53 days old, before moving to display tank -
Video of juveniles feeding at around day 50 -
http://vimeo.com/72547098
So there you go, really easy egg-scattering loaches, and beautiful fish to boot. Highly recommended.