Notes on Hypancistrus debilittera, L129

I like to keep notes and records of what’s going on in my tank, perhaps my experiences with this fish can come in handy for someone else.

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.

Pre-spawning behaviour (one of few photos I have dared to take, these days there is a ban on photography close to the tank):

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 on this forum 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.

Fry development:

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

Andreas

very nice fish andreas, well done and thanks for this very interesting and descriptive write up. I look forward to further updates.

A++++ post
Keep up the great work dude

bart wrote:

A++++ post
Keep up the great work dude

+1 Great post Andreas

Great write up Andreas and a great little pleco.

Hypancistrus are known for there small batches of young. IME it can be anything from 8-25 young.
But this is not a bad thing. If they had a lot of young you would be quickly overrun and there is only so many you can sell on. We see this way to often with so many fish.

If you want the other male to take a cave remove all but 2 caves. 1 for the dominant male and the other for the second male.
The females may never take a cave and if they do it is usually when they are more mature.

Your nervous male should settle down. He is just young and inexperienced.
As you said just shade the entrance of the cave and if you have a reflector on the light twist it to reflect the light to the back of the tank keeping the cave shaded.

Good luck with future spawns.

Darren.

Thanks for the kind comments everyone.

@Darren: Good point about the small batches. I can easily raise these batches without too many grow out tanks and there should not be too much of a panic getting rid of the little ones. I’m wondering if the frequent and regular spawns are a compensation for the smaller batches. As you said they are all young too so the clutch size might grow with age.

I think I’ll remove all but two caves as you suggested to see if the second male reacts on this, thanks for the tip. I will probably leave it until I know the outcome with the current clutch though, in case I would disturb the guarding male.

Thanks for your input, much appreciated!

Andreas

Some good news, it seems that the nervous male only have fanned out a very small amount o fry from this spawn(1-2), the rest are doing well in the cave.

I have not changed anything in the tank, we have however been minding a friends house for some weeks now so he has been left on his own without disturbance.
The male might also have gained some experience from the previous spawns, practice makes perfect.

Andreas