Hi Henrik,
I think all the buckets contain both sexes.
Peckoltia compta are not always very easily sexed soon after being imported.
I would begin by setting up 3 tanks and randomly divide all the fish between the 3 tanks.
I put between 6 and 8 specimens per aquarium and only provide them 2 or 3 spawning caves.
I add smaller pieces of Malaysian aquarium wood in quantities. The pieces designated "small" by sellers are about 30 cm in their longest dimension. I deliberately provide few desirable spawning caves and 5 or 6 pieces of wood in these tanks. As they become fully acclimated the dominant males will take over the available caves and the females will use the caves less and favor hiding places under and around the wood.
I us 20 US gal tanks/~76 liters
Converted to metric they are 12 X 12 X 30 inches = 30 X 30 X ~76 cm =~76 liters.
I originally received wild fish about 7.5 cm in total length. They can breed at that size but mine did not begin to breed until about 2 years after I received and by them they were about 8 to 9 cm in total length. Since then I have had some of my F1 females spawn with wild males when they were 24 months old and about 8 cm in total length. I haven't yet set up a breeding tank for only my 30 month old F1's as I had lost one original wild female and selected what I believed to be 4 females but at best I estimate I am only about correct 70% of the time when sexing fish not in breeding condition. My original five wild fish must haven been at least 6 years old and when they spawn they produce about 25 to 30 fry per brood. The young tank raised females only produced about 15 juveniles per spawn. I expected that and that is why I added 4 more fish to the 2 remaining wild pairs(8 specimens total). It allowed me to end up with about as many fry as 2 males and 3 females older wild fish have produced per year.
Even if you divide them but fail to create groups with a 2 females to 1 male ratio they will spawn and the other adult fish do not harm the fry. I often allow enough spawns to accumulate to 50 to 70 fry before I tear the tank furnishing apart to catch every juvenile. I end up with quite a range of sizes due to their different ages at the time I finally remove them to start over with all the juveniles removed.
I have a lot of aeration between an air stone and air lift driven sponge filter. The other sponge filter is driven by 600 lph power head and the filter/power head in laid on it's side so there is a strong bottom current passing the entrances to the caves at 90* relative to the cave entrances. I also keep the power head/sponge filter horizontal so when I make 2/3 to 3/4 the tank volume water changes the power head remains submerged so I don't have to unplug it.
Mine have bred for 3 consecutive seasons beginning within +/- 2 weeks of March 1st and they have never bred later than +/- 2weeks of Oct 1st. During their "off" season I keep them in tap water. My tap water has changed since I first began but it has always had a pH of 7.4 and the TDS is now 230 ppm but for the first 2 years it tested at about 340 ppm. The city tells me they have changed which well they are using and the water is now a little softer which suits me fine.
Although mine have spawned in tap water my routine has been that beginning a couple weeks before I expect spawning to begin I make 50% water changes using RO water refills until the TDS is between 40 and 75 ppm. The drop of buffering capacity causes the pH to drop to 6.0 to 6.8. I change the water and mix RO and tap throughout my groups breeding season by approximation. I may only change 2/3 of their water during the winter about every 1 or 2 weeks. During breeding season I try to make 1 to 2 water changes per week.
I feed my breeders and fry mainly earth worm sticks, frozen blood worms, Tetra Color Granules and live black worms at night. I place the live black worms in a custard dish. When fry are present they gather over the worms and graze on them constantly. I think the fry rasp the slime and begin digging into the flesh of the worms. A table spoon of worms is all gone within 48 hours. I am sure the adults move in at night.
I never feed the breeders more than 1 or 2 times a day and primarily at night. When fry are present they receive earth worm sticks and frozen blood worms daily. Live black worms are given 4 or 5 times a week.
I believe after you have had more time to observe them you will then be able to more accurately select trios X 2 per tank. That is my goal for the size of tank I use. I actually feed the breeders more in the last months before I expect spawns because once they begin to spawn the males become more reluctant to leave their broods unguarded. I feel it is a good idea to ensure the males are in peak condition prior to their traditional spawning season. My P. compta have always been very seasonal but I do not know if others have the same experience. My group have only produced 3 fry between two different occasions outside their breeding season.
Here is a typical summer time scene and you can see the different sizes between the different aged broods.
Avid Trout fly fisherman. ·´¯`·...¸><)))º>
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