Shane's World Right Reproduction Right Spawning Pseudacanthicus sp. L025, the scarlet cactus pleco

Article © Christophe Girardet, uploaded May 14, 2009.

Pseudacanthicus sp. (L025)Pseudacanthicus sp. (L025)

The beginning
Pseudacanthicus sp. L025, otherwise known as the scarlet cactus pleco has always been a favorite fish of mine. I was dreaming about having a pair of them since 2001, from when I began this crazy fishkeeping odyssey. It's not that easy either, because it's a difficult fish from the point of view of its large size and bad temper. Moreover, as it comes from the Xingu River in Brazil, it's not easy to find several mature individuals. The idea, of course, was to be able to sex them, to obtain a pair with already a dream in the back of my head about a captive spawning!

So, from February 2008, I spread the word around me: I'm looking for mature, wild caught L25. Finally, in late August 2008, a friend of mine called. "Listen, I'm in Germany and I have 10 mature L25 right in the front of me… still interested?", I was asked - my reply was simply, "you bet"! I had, of course, a few questions, did they look healthy? Was it possible to sex them? And finally: how much? I'm always reluctant to buy fishes without having seen them. Anyway, I decided to trust my friend (who has a certain experience of Loricariidae) and decided to let him choose three individuals for me. In the late afternoon, we met on a motorway near my work, when my friend was on his way back home. The deal was struck and in the same day, the plecos were in my 1600 litre tank at home.

Winter 2008-2009, hazardous stimulation
You have to know that in the same tank, I have five Retroculus Xinguensis, which were beginning to show mature sexual behaviour. After a few months, without thinking about the L25, I decided to give my cichlids an adequate substrate to encourage an eventual spawning. I went "fishing" for around 30 litres of pebbles in a river next to my home and I simply laid them straight on to the tanks sandy floor. I guess I was foolish, not thinking that the stones came directly from a European winter time river (around 1°C) into my Xingu tank (around 28 °C). You probably know what came right after this "wild introduction". My Retroculus dug all night long to make a nest (or at least a nice try) and removed the pebbles from one to the other side of the tank. Of course, this caused a huge rise in the nitrate level. From the second day, the water stank! I never thought about the pebbles, but only about an eventual death, I was looking for a big dead fish.

The emergency response was to make a 400 litre rain water change. Finally, I was able to count every inhabitant of the tank, nobody was missing. The big L25 male (on this individual, there's no doubt surrounding gender) is inside a cave, venting. That is to say paddling his ventral fins in a rythmic movement. At first, I think it's because of the pollution and the poor water conditions. However I then discover that this fish is not alone in the cave. I can see a second L25 inside the cave! At this moment, I'm suddenly very anxious because I have no idea about the sex of the second fish. I am unable to know if it's spawning behaviour or a fight for the must-have right cave.

On the next day, the water still stinks. I make another 400 litre rain water change. The temperature falls to 24 °C but it seems the situation is getting better. The two L25 are always together in the tube. I decide to do nothing. Believe me, it's hard not to put your hands inside the tank.

On the 3rd evening, I make a third 400 liter water change, this time, using tap water. The water smells "normal" and I can't see the oily bacterial film on the surface any more. Having a quick look inside the cave, I can see the male is alone, still venting! I'm dreaming, without too much hope I have to admit. It's very difficult to take pictures or even see clearly (remember the cave is 50 cm deep) what is happening inside it. I decide to believe and to leave him alone.

On the fourth evening, the male left the cave which was empty. I only find a few "egg shells". I'm not even sure a clutch was here. But I can now clearly see the female, which has retreated to the back of the tank. She has been hurt a little by her male, but nothing serious, as far as I can see. A few bites marks on the dorsal and caudal fins. Her genital papilla is very much developed. I guess I disturbed them in a way I'm ignorant of, but I still had good hope as she still seemed quite gravid.

One week later: the real deal
On the next Friday, coming back from work, I make my usual fish room check. Of course, I begin by the search of my three favourite fishes. I see what I supposed to be the second male, but no sign of the two others. I'm take out my pocket light and begin to check every cave. In the third I find my pair, venting and shivering close to each other. I don't want to do the same mistake, so I softly step back, and leave them alone.

2nd day
No change! The 2 fishes remain always in the cave. The female seems very quiet, so I'm a bit anxious. I hope the male hasn't killed her. I'd love to post on my favourite sites, but as you know, if you try to announce anything about a spawning, it's the best way to ensure something goes wrong. Therefore its silence and patience.

3rd day
In the morning, before leaving for the job, I can see the female moving. I guess she wants to get out of the cave. But the male doesn't agree, for the moment. In the evening, the male is alone (again), but this time, he's venting an enormous clutch. Even if the cave is very wide, I hardly see the clutch cause the male is covering it with his whole body and fins. It's amazing to see the power of the stream caused by this action, going in and out of the cave.

1st day of guarding eggs
The male is doing a very good job on guarding his clutch. It's very difficult to take pictures especially considering the depth of the cave. The male is really covering his clutch at the very far end of the cave. Moreover, I don't want to disturb him a second time.

4th day of guarding eggs
I really think the only way to leave the father to take care of his clutch is to have a species tank. Yesterday, a Crenicichla female (C. sp Rio Guariquito, a 20 cm species) figured out that there was something delightful inside this cave. The L25 male was fighting to protect his eggs. He was almost completely out of his cave. This evening, same story. I can see this fight causes damage to the clutch which has divided in 3 parts. I can't take the risk of leaving the clutch in this tank with all these troublesome cichlids. I'm not sure it's a good decision, but I steal the clutch from the father.

2nd day of artificial care
It seems my emergency response wasn't adequate. I had no nursery tank ready to put the clutch in and I had to place it in a floating nursery for 48 hours. I prepared a 54 liter tank (sand from another tank and a small canister filter) in a hurry and removed the clutch for a second time in two days. Doing this, I broke a few eggs. I'm anticipating that those two transfers will cause a lot of the eggs not to hatch. It has only been six days from when they were laid and I'm afraid it's too early for a normal hatching. I expect big losses, even with methylen blue treatment.

3rd day of artificial care
This morning, it took me 45 minutes to clean the nursery, destroying the dead eggs or fry. The water is stinking again, as a large part of the clutch and fry are dead in an under filtered 54 litre tank. I guess I lost around 100 eggs or fry in the last 15 hours. Daily water changes will probably be the key. When I left for work this morning, the nursery was clean, no more dead eggs or fry, no more white spot on remaining eggs or fry. But in such poor conditions, I guess I have to expect more losses.

4th day of artificial care
I can't stop this process. Even with daily water changes, even with cleaning the nursery twice a day, my fry go on dying. Every time I come into the fishroom, it's the same desolate picture. It was a very bad idea to collect the clutch so early. I guess I should have left it with the father, even with the cichlids predation. I can think of three root causes:
- too many transfers in too many water conditions
- too much bacteria on the bottom of the emergency nursery, causing a weakness in the eggs and fry
- premature hatching, caused by the 2 first reasons

5th day of artificial care
This morning, I feel slightly better. It seems the process is slower. This morning, I didn't find any dead. I guess I underestimated the initial clutch. I lost around 20-30 eggs — fry per day during 4 days and there are still 77 this morning. On the basis of my Pseudacanthicus sp. L320 spawnings, the hatching should have begun at spawning plus eight days at 28°C. Considering the poor job I did, the hatching begun at day six after the spawning. I guess this would have an impact on the survivors. Today, the survivors have a nice form, the beginning of an eye, a well defined cardio system and some tiny caudal fins.

6th day of artificial care
This hazardous spawning is not very representative, considering the growth rate. I still have around 70 fry, which are in the nursery. I decided to turn the nursery to a bare bottom one. Much easier to check and to maintain.

10th day of artificial care
Yolksacks are getting thinner and thinner. I'm much more confident than a week ago, even if I only have 50 fry left. In the 1600 liters tank, it seems that the original alpha male changed his behaviour. I caused him significant distress stealing his clutch. From an alpha male, he adopted the behaviour of a dominated male. The second has taken his alpha male place. The "father" retired in the background of the tank, where he's fanning inside an empty cave. He rarely gets out for feeding.

19th day
Today, I only took pictures of the fry in the floating nursery. I begun to feed the fry, but I guess it's too early. Could this be a temperature problem?

21st day
I guess 26 °C is not enough for a L025 nursery. The nursery is in my fishroom, right in the flow of the ventilation's room. Even with a heater on 28°C the effective water temperature is around 25-26 °C in the nursery. I have to think about a solution.

23rd day
I finally covered the nursery with a glass. In a couple of hours, the temperature raised to 28°C. What a difference. The fry are getting out of his hiding places, and it finally seems that they eat. 2°C has made a big difference.

30th day
I took my first "out of the tank" shooting session. Finally, there are 32 fry, a poor result! I guess I know what went wrong and I'm going to try another stimulation in this summer. I promise to keep you updated.

Egg clutch3. Egg clutch

Six day old fry4. Six day old fry

Nine day old fry5. Nine day old fry

Twelve day old fry6. Twelve day old fry

Fifteen day old fry7. Fifteen day old fry

Nineteen day old fry8. Nineteen day old fry

Twenty three day old fry9. Twenty three day old fry

Thirty seven day old fry10. Thirty seven day old fry

Forty five day old juvenile11. Forty five day old juvenile

Sixty day old juvenile12. Sixty day old juvenile

Eight two day old juvenile13. Eight two day old juvenile

Ninety four day old juvenile14. Ninety four day old juvenile

Four month old juvenile15. Four month old juvenile

Nursery: Bare bottom or not?
I've read so many opinions about this subject without being able to decide which was the right one for my fish. Some say that a bare bottom is much easier to maintain and others say that a new bacterial film develops on it. On the three previous spawnings (twice L320 and this L25 one) I used a sandy bottom. And each time, I lost more than 80% of the batch. It's probably not only because of the sand or the bottom. The reason is more to find in the poor care I was able to give my fry. But anyway, from the moment I decided to use bare bottom with daily water changes, I haven't had any more losses.

Sexing my Pseudacanthicus
My individuals are only 30 to 35 cm SL, and the tricks I use to sex them are probably only appropriate for individuals of a similar size. Firstly, one looks at body shape. The males are much more thin than the female. They have a longer head section and, on my fishes, the males look more red than dark brown, whereas the female seems more brown than red. The dorsal, caudal and pectoral fins are smaller on the female. It seems that the male use his fins to look bigger and wider. I have observed that the dorsal fin is higher but shorter by my males. I'm not sure it could be a consistent criteria, but the caudal fin lobes of the female is only two to three centimetres long. In males, these lobes are around five to seven centimetres long. Is this a seasonal change? A question of dominance and hierarchy? I've no idea but it's a fact in my tank. Nothing new, but the pectoral fins have very impressive odontodes in the males. They are much thicker and longer on the male where they are much smaller on the female.

2. Male showing odontodal growth2. Male showing odontodal growth

3. Female3. Female

The plecos are fed deep frozen shrimps and pacifica krill (4-5 cm) twice a day. Every two or three days they also get Hikari chips algae waffers and Tetra Prima and I throw in a potato or a zuchini in the tank, but it's more for the Baryancistrus and the Glyptoperichthys, even if I have occasionaly seen an L025 on it. Keeping all these fish in one tank requires a lot of space and the tank is 320x70x70cm and is filtered by two Eheim Pro III 2080 external filters. The water changes are at least once a week around 400 liters (tap water : GH 14 kH 8). These last months, as I make water changes in the nurseries twice a day, the amount of water changes in the big tank is more around 80 liters a day, 7 days a week (30 liters waste water for the L025 nursery and 50 liters for the L320 nursery, immediately replaced by "fresh" water from the big tank).

So, in finishing, that's my breeding tale - I hope you enjoyed reading my experiences with these wonderful fish.

There is further information on this species on the Cat-eLog page.

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