I kept my colony at 90 degrees for almost 6 months. They were fed frozen bloodworms, mysis shrimp, daphnia, and cyclopeeze. Dry foods included New Life Spectrum grow formula, Tetra color bits, Hikari algae wafers, and good quality flake. Live blackworms were added into the mix after about 4 months. They didn't appreciably fatten them up too much, as they were already chubby. They were in a 20 gallon long, with 2 males, and 4 females.
I moved the 6 fish into a 40 gallon long and took pictures of all of them for sexing purposes. (some of which can be found Here. I was told I had everything from all females in the bunch, to mainly males, so I added at that point another "pair" (my guess) from the tank where I had a few younger zebras growing out. The tank is bare bottom, with just enough caves for the males in the tank, and minimal decor for the females to hide in and around, and most of that near the males caves.
The tank volume is turned over close to 20 times an hour, with a large sponge prefiltered powerhead with the venturi wide open and a canister filter. I keep the tank at 86 degrees now. Lights are on a timer for 8 hours a day. The contraption hanging in the front right of the tank is the fry condo's I'm prototyping for use for growing them out without enough tank space to really feed aggressively enough.
My tap water is 7.8 pH out of the tap. The kH is 7 degrees (this fluctuates somewhat) the gH is 9. My TDS is 278 or so. In order to simulate the rainy season, I do a 30% water change with RO water from a barrel that sits on my basement floor with a powerhead running in it. I shoot for dropping the tank temperature 8-10 degrees, and the TDS by 1/3. I try to do the rainy season changes every day for a week, but I've had just 2 or 3 work if I got too busy to finish the season. Especially with the L260, this was the important factor in inducing spawns. I tried all of the same stimulation patterns with tap water and got nowhere for 10 weeks. One big RO change and they spawned within a few days.
Cave size is a VERY important subject for spawning Hypancistrus. I've had a few spawns in caves that are technically too large for the male to block the female in, but they are few and farther between. You want a cave that the male can get in comfortably, so just a smidge taller than his body, and about the width of his body and 1 pectoral fin. (Yes, my husband DID think I was insane when I went down with a ruler and yanked the male out of his cave to see just how big he was!) I make sure the caves are at least 6 inches long from front to back. Larry Vires outlined all this in his online chat lecture and there's really not been much modified with that original plan. The only thing I do differently, is I glue the whole works together with black silicone, let it sit overnight, then I cut the rear wall off again. Take a big rubber band and attach it to the cave with that. Then when you need to pull a spawn, you just hold the cave by the back, put a net or catch container under it, and take off the back carefully. If any fry don't immediately come out, a turkey baster or two full of water can help dislodge them.
Have I forgotten anything?
Barbie
unfortunatly there is no need for any of us to ask another question so the board will now die a death 
I think that you have covered everything. Must get some caves made up, I currently have rocks shaped together to greate tight crevices - hmmm!
