Janne,
It has been my experience that I can plan spawns from these 2 genera, but only if I plan months in advance. I've kept Panaque maccus, Panaque sp. L002, and Peckoltia vitatta spawning year round. However, it took a lot of attention to detail to do it. Normally, I start dry seasons on juveniles once I've had them for about 6 months. Experience has taught me that most of the small fish shipped in for the hobby are no less than 3 months old. I continue that first dry season for a full 3 months, pushing as much food into them as I can get them to take. It's not uncommon that the temp for low-land species rises above 90'F during those 3 months. I normally shoot for ~85'F. For fish from higer elevations, I keep them slightly below 80'F.
If they do not spawn that first rainy season, which is actually just a series of week of water changes and a week without, I start them on a second 3 month period. The "rainy" seasons are done for 6 weeks at a time. Once they have started spawning, I can usually keep them going by following the week on / week off schedule.
It may also be pertainant to mention that a lot of breeders which never breed, aside from the 2 genera being talked about, will start if given a longer dry season. I've recieved emails and calls from several breeders who are convinced that only a small portion of their fish are capable of spawning. It is a common mis-conception with Hypancistrus zebra. If given a longer dry season, most will come into the rythm the first cycle if they are actually mature. I believe that the fish which are spawning with the short dry seasons are just the ones that are more inclined to spawn regardless of the circumstance. The "guppies" of the catfish world
Larry Vires
Impossible only means that somebody hasn't done it correctly yet.
? I'm trying to find some easy plecos to breed. I'm planing to buy a 700l tank and place there some easy breeding plecos. I would like to buy L-46 but it's too expencive in Finland 
. Here is some plecos i like.
So when the autum comes late in oktober I start changing the hardness and let the pH drop a bit and that takes no longer then 3-4 weeks before the Peckoltia start to spawn but the Panaque will take longer, I cant say that this works for everyone of these families because species from Peru or Colombia always breed in late spring or beginning of the summer in my tanks. Hypancistrus species just seems to breed all year around if they have the right habitat in the tank wich is fast current and high water quality. I have a pair of L-239 and they did a breeding attempt last year in july and after that not showing any more interest but now again they start to be very active again and the female are pregnant so I hope for success with these in some weeks. I also have some L-204 that are showing their breedings behaviour right now and I keept 1 male with 2 females there both are pregnant for some weeks but nothing has happend so far so today I moved one of the females because they are fighting between each other about the male and that disturb them I think...so we will see what happens following days/weeks if I have right about them.
The 750l is too big to fitt in my room. My parents won't let me throw away my desk. The max lenght is 160 cm. My parents won't let me keep the aquarium in a room that has got an wooden floor. I'm giving the 180l tank to my littlebrother as soon as i will get a bigger tank,
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