Corydoras mystery fry

These two came out with a water change today, they are either Corydoras concolor or habrosus. I have not bred either before so it's good either way.

Does anyone know which species they are?

Hypancistrus debilittera, L129; fry development

I just fished out these little lads from their parent’s tank. They are from one of my first spawns of Hypancistrus debilittera, L129 and I believe that I managed to catch roughly two thirds from that batch.

It is very important for the growth and well-being of young plecos that they are not kept in too crowded conditions. Even more so when several batches share the tank as the smaller ones will have a very tough time competing for food and hiding spots against their larger siblings. 

These fish were moved so that their younger siblings can get a chance to grow properly and become strong little fishes.They have now moved to a 72 litre tank with strong filtration and plenty of hiding spots.

Notes on breeding Hypancistrus debilittera, L129

There are three positive sides which made me decide on this species; it’s small, beautiful and relatively affordable compared to many other L-numbers. Its small size makes it easy to keep a decent sized group. The males have showed very little aggression so far which also helps.

The group was bought from Seahorse Aquariums in the beginning of June 2013 and consists of two males and three females. The individuals were wild caught young adults in good condition which made it easy to sex them by viewing them from above. The males had a distinct V-shape and showed “hairy” odontodal growth along the lower body, the females were quite plump in comparison. I have been wrong many times when sexing plecos but these were quite easy (or I got lucky).

The group reside in my 125 litre corner tank along with 12 Ember Tetras and some Otocinclus cocama.
The tank is filtered by a small air driven sponge filter as well as a 600 L/H powerhead with a large sponge, the powerhead creates a moderate currents which flows along the front glass of the tank.

Readings:
Temp 26°C
pH 6-6.5
German hardness °dH 3

Wood and roots comprise the furniture as well as six small sized (often used for L046) breeding caves plus a few coconuts.
The dominant male chose a cave near the front of the tank with the entrance exposed to the current. Strangely the second male never settled in one particular cave. The females seem to prefer roots and coconut shells as temporary hiding spots.

Four spawns have taken place so far with a few weeks in between each. It looks like the females take turns to mate with the dominant male. The male has only guarded one clutch at a time compared to for instance common Ancistrus where the male can guard clutches from several females at the same time.

This is the point where I started to have problems. The tank is not a dedicated breeding tank hidden away from disturbance, its placed in the living room. Any disturbance such as a water change or a lot of movement in the room has triggered the male to eat the larva and fortunately in the process “fanning out” some of them that could be rescued.

The last time I witnessed the event it was extremely frustrating watching dead larva with their yolk sacks eaten being flushed out from the cave. The cluthes seems quite small, I'm not sure exactly but it seems that the egg count have been around 10-15 max, maybe less.

Both Darren and Bart from www.irishfishkeepers.com have advised to cover the tank and this would probably work. I would however prefer to find another solution as the tank was supposed to be a “display tank”. Before going down this route I will cover up the males cave with roots and hope that this will make him feel a bit more secure and obscure his line of sight from movement in the room. The male is also young (possibly first spawns) and he might get more comfortable in time.

Not all was lost though as I have managed to catch some of the newly hatched larva that were flushed out. These were raised without problems in the floating breeding trap above, they grew fast and at a length of about 2cm TL they were released back into the tank to fend for themselves. The breeding trap was cleaned once per day; the sides were gently brushed with a tooth brush and uneaten food was removed with a turkey baster. The fry were fed twice per day with a variation of dry foods. The box also contained oak leafs which the fry seemed to feed greedily from. Fresh water from the main tank was flushed into the box trough a small air-lift sponge filter. I let few snails reside in the breeder box as a clean up crew for any uneaten food that i might have missed.

I’ll update this post if there is any news on the nervous male, he is at the moment guarding a new batch so fingers crossed.

Update 1:

 I just fished out these little lads from their parent’s tank. They are from one of my first spawns of Hypancistrus debilittera, L129 and I believe that I managed to catch roughly two thirds from that batch.

It is very important for the growth and well-being of young plecos that they are not kept in too crowded conditions. Even more so when several batches share the tank as the smaller ones will have a very tough time competing for food and hiding spots against their larger siblings. 

These fish were moved so that their younger siblings can get a chance to grow properly and become strong little fishes.They have now moved to a 72 litre tank with strong filtration and plenty of hiding spots.




Update 2:
After the spawns described above the male calmed down and started to raise the fry himself, no further intervention was needed and the fish now spawn regularly once per month.

D.I.Y. simple fry rearing box

This is a very simple, cheap but effective fry rearing box. This example does not have proper floating supports as it's resting on a root in my tank. Floating support or something to anchor the box to the side of an aquarium would be easy to ad.

What you need: plastic box with a lip at the top to hold some air, silicone, carpet knife, filter foam, and a spare small airlift filter:

A hole was cut at one end of the box and sealed with filter foam, attached with silicone. This will drain the box and keep the water level the same as in the tank it is in. The air driven filter will pump in fresh water from the tank into the box:

Side view:

In tank:

From above:

This is a variation of a design that has been used by aquarists for many years. 

The benefit of this type is that air driven filter constantly supplies the fry/eggs with fresh water from the same tank that they originally were laid in/hatched in. This method also keeps the water conditions stable which is extremely important with fragile fish, something that can be harder to achieve in a small 
separate tank.

Another benefit is that the breeder box makes it easy to make sure that the fry eat, the small space makes it possible to target feed fry while fry in a larger tank might not even find the food in time.

Maintenance of the rearing box is still important though and uneaten food and bacteria on the sides should be removed/cleaned on a regular basis. A turkey baster works quite well for this purpose, and a tooth brush can be used to clean the sides.

Depending on species and strength of the air pump used it can also be a good idea to add an air stone for increased water circulation.

Personally I use this type for plecos and corys; I ad gravel/sand from the main tank, some small plants/moss/roots/oak leafs/ for the fry to hide in.

Remember that we want the fry to feel comfortable and not stressed as this increases their growth rate and lowers the risks of deaths.
 

Update; L129, Hypancistrus debilittera fry

The fry of my L129, Hypancistrus debilittera that were kicked out from the cave as larva on the 30th of September are now 10 days old and are doing very well.

There is still the six of them residing in a small floating container. As the breeding box I had planned to use for this type of situations broke recently I'm in the process of building a new one which if it works well will be presented as a DIY post here in the future.

As you can see from the rounded bellies and yellow coloration the fry are still absorbing their yolk sacks, the critical stage in rearing pleco fry starts when they are ready to eat as they need allot of food that easily pollute the water if uneaten.

I'll keep you posted on the progress with these.